Exhibit 4.55



This is an English translation



Agreement No.:

121200102034













International Electronic Headquarters of
the Electronic Zone

Qihu 360 Headquarters Program







Purchase Agreement for

Floors 1-4 of Tower A























Beijing Electronic Zone Co., Ltd.

Beijing Qichuang Yousheng Keji Co., Ltd.







August 31, 2012

Beijing











Party A: Beijing Electronic Zone Co., Ltd.

Address: A 12 Jiuxianqiao Road, Chaoyang
District, Beijing

Zip Code: 100015

Business License No: 110000005030270

Legal Representative and Person in Charge:
Wang Yan Contact Tel.: 010-58833501



Party B: Beijing Qichuang Yousheng Keji
Co., Ltd.

Address: Room 517, Block 46, No. 9 Radio
Components Factory (2-1), Shengou Village, Chaoyang District, Beijing

Zip Code: 100025

Business License No: 110105015122088

Legal Representative and Person in Charge:
Chen Zhengyu              Contact Tel.: 58781000



Whereas:

1.	Party A has undertaken
the reconstruction of the Electronic Zone as an old industrial base, and the construction of the East Area of the Electronic Zone
in Zhongguancun Science Park, as well as investment solicitation thereof.



1.1	Party A has
legally obtained the land use rights to the state-owned land 3# with a size of 19,669.36 square meters (usable floor area) at the
International Electronic Headquarters of the Electronic Zone (Land Use Right Certificate: Jing Chao Guo Yong (2007) No. 0479; land
use: research and development; expiration date: December 8, 2056).



1.2	Party A warrants
that the state-owned land use rights regarding the Property (as defined herein) under this Agreement and the construction in progress
are free from any pledge, lawsuit, arbitration or other limitation of rights.



1.3	Party A has
obtained the approval for the Project of Building 2# on Land 3# from the competent authorities, the Planned Permit of Building
(No.: Jian Zi No. 110000200900546, 2009 Gui Jian Zi No. 0214) and the Building Construction Permit (No.: [2010] Shi [Chao] Jian
Zi No. 0198).



1.4	As of the date
of this Agreement, Party B was informed that the main body, electrical and mechanical engineering and architectural curtain wall
of the Property had been completed and the outdoor landscaping was under construction. Party B agrees to purchase the Property
subject to Appendix 5 “Standards on Delivery of the Property” of this Agreement.



2.	As a leading
internet security software product and service provider, Party B meets the industrial guidance of the Science Park of the Electronic
Zone in respect of industrial positioning and business. Upon fully understanding the project of “International Electronic
Headquarters of Zhongguancun Electronic Zone” as well as other information concerned, Party B decides to purchase Building
2# on Land 3# in the International Electronic Headquarters from Party A to locate its headquarters and use the Property for the
approved purposes and undertakes that it will register the Property as its principal office and for the purpose of tax payment
after entry.



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Both parties have reached
the following agreement through negotiation based on equality, voluntariness and fairness and in accordance with the relevant laws
and regulations.



Article 1 The Property



1.1	Scope of the
Property:



For the purpose of
this Agreement, the “Property” refers toFloors 1-4, Tower A, Building 2# on Land 3# at International Electronic
Headquarters, Jiuxianqiao Road, Chaoyang District, Beijing (see Appendix 1). The main body of the building is a frame-shear
structure with 19 floors. The Property consists of floors 1-4 above the ground floor of the west wing. The gross floor area
of the Property is estimated at 7,787.36 square meters.



See Appendix 2 for
details. The area indicated above shall be subject to registration in the Certificate of Title.



1.2	Confirmation
of Area of the Property:



The gross floor area
of the Property is estimated at 7,787.36 square meters (see Appendix 3 for details). Both parties agree that the floor area
will be for reference only whereas the actual floor area of the Property shall be subject to the confirmed area to be registered
under the relevant Certificate of Title.



Article 2 Purchase
Consideration of the Property and Schedule of Payment



2.1	Consideration
of the Property:



The purchase consideration
of the Property shall be RMB20,000 (RMB Twenty Thousand) per square meter of gross floor area and is estimated to be RMB155,747,200
(RMB One Hundred and Fifty Five Million Seven Hundred and Forty Seven Thousand and Two Hundred) (the “Purchase Consideration”)
which is calculated on the basis of the estimated gross floor area.



2.2	Payment



The final price shall
be adjusted and settled according to the said registered title area, and in case of any divergence between the contractual area
and such registered title area, the latter shall prevail. The payment shall be settled within 30 working days after completion
of the title registration from both parties and agreement of the purchase consideration adjustment (if any) in writing.



2.3	Schedule of
Payment



Party B will settle
the Purchase Consideration by installments.



The schedule of payment
shall be as follows:



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2.3.1	Party B shall
pay five percent (5%) of the Purchase Consideration, i.e., RMB7,787,360 (RMB Seven Million Seven Hundred and Eighty Seven
Thousand and Three Hundred and Sixty) to Party A within 30 working days after execution of this Agreement).



2.3.2	Party B shall
pay fifteen percent (15%) of the Purchase Consideration, i.e., RMB23,362,080 (RMB Twenty Three Million Three Hundred and
Sixty Two Thousand and Eighty) to Party A before August 31, 2013.



2.3.3	Party B shall
pay the remaining eighty percent (80%) of the Purchase Consideration, i.e., RMB124,597,760 (RMB One Hundred and Twenty Four
Million Five Hundred and Ninety Seven Thousand and Seven Hundred and Sixty) to Party A before January 31, 2014.



2.4	Both parties
agree that Party A shall issue an official invoice to Party B upon receipt of the total Purchase Consideration paid by Party B
pursuant to the schedule prescribed in Article 2.3.



2.5	Party A’s
Bank Account:



Party A notifies Party
B to directly remit the said installments to Party A’s bank account, details of which are as follows:

A/C bank: Electronic
Zone Science Park Branch, China Construction Bank

Account name: Beijing
Electronic Zone Co., Ltd.

Account No:



Article 3 Delivery
of the Property



3.1	Party A shall
complete construction and inspection of the Property before February 10, 2014 (hereinafter referred to as the “agreed
date of delivery”) and notify Party B to acknowledge acceptance of the Property in writing twenty (20) working days prior
to the agreed date of delivery. Party A shall be entitled to refuse delivery of the Property without any liability for delay of
delivery in the case Party B has caused any delay in payment of the Purchase Consideration and Party A fails to receive the agreed
amount before the agreed date of delivery. The following standards shall be satisfied upon delivery of the Property:



(1)	The Property
being completed and be deliverable;

(2)	The Approval
for Acceptance of Planning and the Form of Final Completion for Filing regarding the Property being obtained;

(3)	The utilities
of water supply and power supply and elevators are in working order;

(4)	All other facilities
of the Property shall reach the standards for delivery as prescribed in Appendix 5; and

(5)	The Property
shall satisfy other legal standards for completion and comprehensive inspection.



When delivering
the Property, Party A shall provide Party B with the construction and project materials related to the Property, including:



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(1)	Final acceptance
materials, such as the general plan of completed projects and as-built drawings of single building, structure, equipment and supported
facilities;

(2)	Copies of the
Form of Final Completion for Filing; and

(3)	Other materials
relevant to the Property and the property management thereof.



3.2	Party B shall
inspect the Property within twenty (20) working days after receiving Party A’s delivery notice and shall issue an acceptance
notice if the Property passes the acceptance inspection. In the case where the Property has been found in violation with any requirement
under national or local laws, regulations, rules and norms concerned, or as well as Appendix 5 during inspection, Party B shall
issue a rectification notice in writing. Party A shall complete such rectification within one month; if impossible, it shall provide
a written rectification commitment to Party B, assuring Party B of the term of rectification and quality. If Party B believes the
Property, after rectification, is in material violation with any relevant laws and regulations, or significantly inconsistent with
the delivery standards and may actually affect the legal rights and interests of Party B, Party B may appoint an evaluation agency
acceptable to both parties to conduct an evaluation. If Party B’s opinion is confirmed after evaluation, Party B shall be
entitled to refuse delivery by sending a written notice to Party A and the liabilities for delay of delivery as well as the evaluation
fees shall be borne by Party A. Otherwise, Party B shall bear the evaluation fees.



3.3	Failure of Party
B to issue an acceptance notice or a written rectification notice within 20 working days after Party A issues the delivery notice
shall be deemed as acceptance by Party B of the Property.



3.4	Both parties
shall execute the Delivery Receipt of the Property after the inspection and acceptance of the Property. The date of the Delivery
Receipt of the Property shall be deemed as the date of actual delivery of the Property (hereinafter referred to as the “actual
delivery date”) and Party A shall be deemed performed of its obligation of delivery. If Party B delays execution of or is
reluctant to execute the Delivery Receipt of the Property after the Property after the inspection and acceptance of the Property,
or if Party A provides the rectification commitment, it shall be deemed that Party A has performed its obligation of delivery.



3.5	Both parties
agree that any and all risks of damage and loss of the Property shall be transferred to Party B and any and all expenses related
to the Property, including property management fees and utilities fees, shall be borne by Party B from the actual delivery date.
Party B shall assume any and all liabilities and obligations stipulated in the rules of the property management company concerning
property use, management and maintenance.



3.6	If the Property
fails to be delivered before or on the agreed date of delivery due to any fault on the part of Party B, the risks and expenses
incurred during this period, including damage or loss of the Property and property management fee, shall be assumed by Party B.



3.7	Both parties
shall separately execute a maintenance agreement.



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3.8	Party B shall
have the right to name the Property or set up its trade name, logo, nameplate, direction boards or billboards on the roof or on
the external wall of or around the Property, provided that the specific plan on such naming and setup shall be subject to the consent
of Party A and be harmonious with the overall planning of the International Electronic Headquarters and conform to the requirements
by the competent authorities in this regard. Party B shall be liable for going through relevant approval procedures and Party A
promises to provide relevant documents and certifications. All the expenses arising from or related to such approval and examination
procedures shall be borne by Party B.



3.9	Given the titles
of the building, of which the Property is a part, and the corresponding underground parking area belongs to Party A, Party A agree
to lease the remaining parking lots to Party B in the proportion of the area it bought after appropriating several public parking
lots;



3.9.1	Party A may
determine the specific position of such parking lots in the principle of a near position to the Property;



3.9.2	Party A shall
grant rent concession to Party B;



3.9.3	The parking
lots rent by Party B may not be used for other purposes except for parking by employees of Party B; and



3.9.4	The number,
position and rent of the parking lots shall be separately negotiated by both parties.



3.10	Party B agrees
to appoint Party A’s property management company to provide property management services, which may be separately stipulated
in the Property Management Service Agreement.



Article 4 Certificate
of Title



4.1	Party A shall
guarantee to obtain the Certificate of Title in Party B’s name within three (3) years after delivery of the Property, provided
that Party A receives the price due in full amount (except for the balance for difference between the estimated and actual areas)
and complete documents required. If Party A delays or fails to obtain the Certificate of Title due to any fault on the part of
Party B, including but without limitation to failure of Party B to pay any taxes or fees, Party A will not assume any breach liabilities,
except for assistance to obtain the Certificate of Tile.



4.2	Both parties
agree that the taxes and fees incurred during the process of obtaining the Certificate of Title shall be assumed by both parties
respectively pursuant to relevant national provisions.



4.3	Since the Property
is located in the Scientific Park of Zhongguancun Electronic Zone, Party B is not allowed to transfer it in accordance with the
relevant provisions in principle; if transfer is necessary, Party B shall give a prior notice to Party A and Party A shall have
the preemptive rights under the same conditions.



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Article 5 Liabilities
for Breach



5.1	Principle



Both parties shall
enjoy and perform the rights and obligations as stipulated in this Agreement in good faith. In case of any breach of this Agreement,
the default party shall assume its breach liabilities and pay damages to the non-default party. The express provisions on percentage
of damages stipulated in this Agreement, if any, shall be executed. If both parties breach the Agreement, each party shall respectively
assume its liabilities according to the extent or severity of its fault.



The non-default party
shall be entitled to require the default party to make corrections and any legal liabilities arising thereof shall be assumed by
the default party.



5.2	Party A’s
Liabilities for Breach



The following provisions
shall apply if Party A fails to perform any of its obligations within the time limits as stipulated in this Agreement:



5.2.1	Party A shall
pay Party B the damages equal to 0.01% of the amount paid by Party B per day if the Property failed to be delivered to Party B
before or on the agreed date of delivery due to any fault on the part of Party A. Party B shall be entitled to cancel this Agreement
if the Property has not been delivered more than 180 days after the agreed date of delivery. If Party B cancels this Agreement,
Party A shall refund the amount paid by Party B within 30 days from the date of Party B’s notice on cancellation of the agreement
and pay the damages equal to ten percent (10%) of the total price of this Agreement to Party B. If Party B does not choose to cancel
this Agreement, Party A shall pay Party B the damages equal to 0.01% of the amount paid by Party B per day from the next day to
the agreed date of delivery and until the actual delivery date, and this Agreement shall continue to be performed.



5.2.2	Party A shall
pay Party B the damages equal to 0.01% of the amount paid by Party B per day if Party A fails to perform its obligation under Article
4.1 due to any fault on the part of Party A. Party B shall be entitled to cancel this Agreement if Party A fails to perform such
obligation more than 180 days after the agreed date. If Party B cancels this Agreement, Party A shall refund the amount paid by
Party B within 30 days from the date of Party B’s notice on cancellation of the agreement and pay the damages equal to ten
percent (10%) of the total price of this Agreement to Party B.



5.2.3	Except as
otherwise stipulated herein, Party A undertakes that it will not resell the Property to others and it has not and will not create
any mortgage over the Property; otherwise, Party A shall pay the damages equal to thirty percent (30%) of the total price of this
Agreement to Party B and continue to perform this Agreement at Party B’s discretion.



5.3	Party B’s
Liabilities for Breach



The following provisions
shall apply if Party B fails to perform any of its obligations within the time limits as stipulated in this Agreement:



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5.3.1	If Party B
fails to pay any amount within 180 days after the date of payment due to any fault on the part of Party B, Party B shall
pay the damages equal to 0.01% of the amount due per day to Party A from the next day to the date of payment as stipulated in this
Agreement and until the amount due is paid in full amount and this Agreement shall continue to be performed.



5.3.2	Party B agrees
that if Party B does not pay any amount due more than 180 days after the date of payment due to any fault on the part of Party
B, Party A may cancel this Agreement, resell the Property to any person and refund the amount paid by Party B, and Party B shall
pay Party A the damages equal to ten percent (10%) of the total price of this Agreement. If Party A does not choose to cancel this
Agreement, Party B shall pay Party A the damages equal to 0.01% of the amount overdue per day from the next day to the date of
payment as stipulated in this Agreement and until the amount due is paid in full amount and this Agreement shall continue to be
performed.



5.4	Except as specifically
stipulated in Article 6 herein and exercise by either party of its right to unilaterally cancel this Agreement pursuant to the
Agreement, neither party may terminate this Agreement without cause. Any party who cancels this Agreement for causes other than
legal provision or agreements herein shall pay the other party damages equal to ten percent (10%) of the total price of this Agreement.



5.5	Any party who
has to refund all amounts and/or pay damages to the other party pursuant to this Agreement due to its breach of the Agreement,
shall refund all amounts as stipulated in the Agreement and pay such damages within thirty (30) days after receiving the written
notice from the non-default party; otherwise, the default party shall pay the non-default party damages equal to 0.01% of the total
price per day from the date when it shall pay such damages and until the damages are paid in full amount.



Both parties acknowledge
that the non-default party shall be entitled to deduct the damages or other compensations for damage that the default party shall
pay pursuant to the Agreement from the amounts payable or receivable.



Article 6 Termination
of Agreement



6.1	This Agreement
may:



(1)	be early terminated
if both parties reach a new agreement in writing through negotiations;

(2)	be automatically
terminated after both parties fully perform their obligations;

(3)	be terminated
by one party by sending a written notice to the other party who is or becomes legally incapable of continuing to perform this Agreement
due to bankruptcy, wind-up or cancellation of business license;

(4)	be terminated
by either party by sending a notice to the other party if this Agreement cannot be performed due to any force majeure event; or

(5)	be terminated
or cancelled due to other reasons as stipulated in laws, regulations or this Agreement.



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6.2	Either party
who terminates or cancels this Agreement pursuant to laws or regulations or this Agreement, shall issue a written notice of termination
or cancellation to the other party, and this Agreement shall be terminated or cancelled upon receipt of such notice by the other
party. The non-default party shall be entitled to make claims against the other party in accordance with laws, regulations and
this Agreement.



Article 7 Confidentiality



7.1	Except as otherwise
stipulated in this Agreement, laws and regulations and provisions of stock exchanges, each party shall, at any time after the date
of this Agreement, keep confidential the following information it obtains in the process of negotiation, execution and performance
of this Agreement (hereinafter referred to as the “confidential information”) and may not disclose such information
to a third party or use such information for purposes other than stipulated in this Agreement without prior written consent of
the other party:



(1)	Any information
related to negotiations concerning this Agreement;

(2)	Any information
related to any trade or term under this Agreement; and

(3)	Any information
related to both parties to this Agreement and their affiliates.



7.2	Each party shall
cause its employees, officials, representatives or agents, professional consultants or other affiliates or associated persons to
perform the confidential obligation under Article 7.1 herein and prohibits the persons who access to such information from using
such confidential information for any business activities irrelevant to this Agreement.



7.3	The confidentiality
obligation under Article 7 shall not apply to such confidential information that:



(1)	has been or
is known to the public before disclosure by the other party;

(2)	is required
to be disclosed or used by mandatory provisions of law or by court;

(3)	is disclosed
or used with the prior written consent of the other party; or

(4)	is announced
or disclosed in accordance with this Agreement or for the purpose of fulfilling the transactions under this Agreement (including
announcement in the trading system).



7.4	The confidentiality
obligation under this Agreement shall survive the termination of this Agreement.



Article 8 Force
Majeure



8.1	A force majeure
event refers to any event that is unpredictable, inevitable and uncontrollable and may prevent the performance of this Agreement,
including but without limitation to such natural disasters as flood and earthquake and such social events as war, strike, riot,
and promulgation of new laws and regulations and launch of new policies, administrative measures by government and governmental
acts.



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8.2	In case of any
force majeure event, the affected party shall notify the other party of the force majeure event in a timely manner and provide
the proving document issued by relevant organs in the place where the event occurs within 14 days after the force majeure event
occurs. In addition, both parties shall do their utmost to take necessary measures to reduce the impacts of such force majeure
event. The prevented party shall notify the other party in a timely manner after the impact of such force majeure event eliminates.



8.3	Except as otherwise
provided for by law, either party who is prevented from performing this Agreement by force majeure may be exempted from any breach
liabilities according to the impacts of such force majeure.



Article 9 Effectiveness
and Version



9.1	This Agreement
shall enter into force upon signature and seal by both parties.



9.2	This Agreement
has been prepared in six (6) originals and each party keeps three (3) of them, which shall be of equal legal force.



Article 10 Dispute
Settlement



10.1	 Any dispute
between both parties shall be settled through negotiations; if a negotiation fails, the dispute may be filed to the People’s
court for settlement in the place where the Property is located in accordance with the laws and regulations of the People’s
Republic of China.



Article 11 Appendixes
to the Agreement



| | Appendix 1: | Location of International Electronic Headquarters
| | ----------- | -------------------------------------------------

| | Appendix 2: | General Plan of Land 3# in International Electronic Headquarters
| | ----------- | ----------------------------------------------------------------

| | Appendix 3: | Technical Report on Estimation of the Area of Building
2# on Land 3# in International Electronic Headquarters (subject to the report with the special stamp for mapping results submitted
for filing)
| | ----------- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| | Appendix 4: | Copies of Business License of Both Parties (with Official
Stamps)
| | ----------- | -----------------------------------------------------------------

| | Appendix 5: | Standards on Delivery of the Property
| | ----------- | -------------------------------------

| | Appendix 6: | Planning of Property (for reference only and subject
to as-built drawings)
| | ----------- | --------------------------------------------------------------------------



Party A: Beijing Electronic Zone Co., Ltd.

(Company Chop):	       	/s/ [Company Stamp of Beijing Electronic Zone Co., Ltd.]

Legal (Authorized) Representative:	       /s/

Signing Date:	       August 31, 2012 in Beijing



Party B: Beijing Qichuang Yousheng Keji
Co., Ltd.

(Company Chop):	       /s/ [Company Stamp of Beijing Qichuang Yousheng Keji Co., Ltd.]

Legal (Authorized) Representative:	       /s/

Signing Date:	       August 31, 2012 in Beijing



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