U.S. SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549










FORM 40-F/A








(Amendment No. 1)











Check One



☐Registration Statement Pursuant to Section 12 of the Securities Exchange
Act of 1934



☒Annual Report Pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of
1934

For the fiscal year ended December 31, 2019

Commission File Number: 001-38141



Sierra Metals Inc.

(Exact name of Registrant as specified in its charter)

N/A

(Translation of Registrant’s name into English (if
applicable))



Canada

(Province or other jurisdiction of incorporation or organization)



1021

(Primary Standard Industrial Classification Code Number (if
applicable))



N/A

(I.R.S. Employer Identification Number (if applicable))

|161 Bay Street, Suite 4260, Toronto, Ontario M5J 2S1, (416) 366-7777
|--------------------------------------------------------------------

(Address and telephone number of Registrant’s principal
executive offices)

|Cogency Global Inc.                                                
|-------------------------------------------------------------------
|10 East 40th Street, 10th Floor, New York, NY 10016, (800) 221-0102

(Name, address (including zip code) and telephone number
(including area code of agent

for service in the United States)

Securities registered or to be registered pursuant to Section
12(b) of the Act.

|Common Shares       |  | NYSE American                            
|------------------- |  | -----------------------------------------
|Title of each class |  | Name of each exchange on which registered



Securities registered or to be registered pursuant to Section
12(g) of the Act.



None

(Title of Class)



Securities for which there is a reporting obligation pursuant
to Section 15(d) of the Act.



None

(Title of Class)





For annual reports, indicate by check mark the information filed with this Form:

☒
Annual information form☒
Audited annual financial statements



Indicate the number of outstanding shares of each of the issuer’s classes
of capital or common stock as of the close of the period covered by the annual report:



Common Shares: 162,115,379



Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 of 15(d) of the Exchange Act during the preceding 12 months (or for such shorter period that the Registrant
was required to file such reports) and (2) has been subject to such filing requirements for the past 90 days.



Yes☒No ̈



Indicate by check mark whether the registrant has submitted electronically every
Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter)
during the preceding 12 months (or for such shorter period that the Registrant was required to submit and post such files).



YesxNo ̈





Indicate by check mark whether the registrant is an emerging growth company as
defined in Rule 12b-2 of the Exchange Act.



Emerging
growth company☒



If an emerging growth company that prepares its financial statements in accordance
with U.S. GAAP, indicate by checkmark if the registrant has elected not to use the extended transition period for complying with
any new or revised financial accounting standards† provided pursuant to Section 13(a) of the Exchange Act.

 ̈

Not applicable






















EXPLANATORY NOTE



This Amendment No. 1 on Form 40-F/A amends Sierra Metals Inc.
(the “Company”)’s Annual Report on Form 40-F for the year ended December 31, 2019, originally filed with the
U.S. Securities and Exchange Commission (the “SEC” or the “Commission”) on March 30, 2020 (the “Original
Filing”). The Company is filing this Amendment No. 1 to amend the Management’s Discussion and Analysis filed with the
Original Filing.



Except as described above, no other changes have been made
to the Original Filing. The Original Filing continues to speak as of the date of the Original Filing, and the Company has not
updated the disclosures contained therein to reflect any events that occurred at a date subsequent to the filing of the Original
Filing other than as expressly indicated in this Amendment No. 1. Accordingly, this Amendment No. 1 should be read in conjunction
with the Original Filing and the Company’s other SEC filings.





2







SIGNATURES





Pursuant to the requirements of the Exchange Act, the registrant
certifies that it meets all of the requirements for filing on Form 40-F/A and has duly caused this Form 40-F/A to be signed on
its behalf by the undersigned, thereto duly authorized.





| | SIERRA
    METALS INC.
| | ----------------------
| |                       
| |                       
| | By:                   
| |                       
| |                       





Dated: April 1, 2020



3







EXHIBITS



The following documents are filed as exhibits to this Form 40-F/A:



|Exhibit Number     | Document                                                                                                                                                
|------------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------
|                   |                                                                                                                                                         
|Certifications     |                                                                                                                                                         
|13.1               | Certifications of the Chief Executive Officer and Chief Financial Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 dated April 1, 2020 
|13.2               | Certifications of the Chief Executive Officer and Chief Financial Officer pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 dated April  1, 2020
|Annual Information |                                                                                                                                                         
|99.1               | Amended
    Management’s Discussion and Analysis for the year ended December 31, 2019