<PAGE>   1
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM 10-K

[X]      Annual Report Pursuant to Section 13 or 15(d) of the Securities
         Exchange Act of 1934 For the fiscal year ended December 31, 1996

[  ]     Transition Report Pursuant to Section 13 or 15(d) of the Securities 
         Exchange Act of 1934

                        Commission File Number 1-3423-01

                             ENRON CAPITAL TRUST II
             (Exact name of registrant as specified in its charter)



               Delaware                              76-6122939
     (State or other jurisdiction         (IRS Employer Identification No.)
  of incorporation or organization)

                    
                     1400 Smith Street, Houston Texas 77002
               (Address of principal executive offices) (Zip Code)

                                 (713) 853-6161
              (Registrant's telephone number, including area code)

Securities registered pursuant                    Name of Exchange on
to Section 12(b) of the Act:                       which registered:

8 1/8% Trust Preferred Securities                New York Stock Exchange
        (Title of Class)

           Securities registered pursuant to Section 12(g) of the Act:

                                      None

   Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 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.
                                            [X] Yes               [  ] No

   Indicate by check mark if disclosure of delinquent filers pursuant to Item 
405 of Regulation S-K is not contained herein, and will not be contained, to 
the best of registrant's knowledge, in definitive proxy or information
statements incorporated by reference in Part III of this Form 10-K or any 
amendment to this Form 10-K. [X]

   As of January 31, 1997,  the  registrant  had an aggregate of 6,000,000 
8 1/8% Trust  Preferred  Securities  and 186,000 8 1/8% Trust Common 
Securities outstanding.

                       DOCUMENTS INCORPORATED BY REFERENCE

None.



<PAGE>   2



                                     PART I


ITEM 1.  BUSINESS.

         Enron Capital Trust II (the "Trust") is a statutory business trust
created under the Delaware Business Trust Act, as amended (the "Trust Act"),
pursuant to an amended and restated declaration of trust (the "Declaration") and
the filing of a certificate of trust with the Secretary of State of the State of
Delaware. As of December 31, 1996, the Trust had no assets or operations. On
January 16, 1997, the Trust completed its initial public offering of the Trust
Preferred Securities described below, as a result of which the Trust's sole
assets are 6,186,000 8 1/8% Partnership Preferred Securities ($25 liquidation
amount per security) representing an 85% limited partnership interest in Enron
Preferred Funding II, L.P., a Delaware limited partnership (the "Partnership").
Ownership of the assets of the Trust is evidenced by an aggregate of 6,000,000 8
1/8% Trust Preferred Securities (the "Trust Preferred Securities"), which are
listed and traded on the New York Stock Exchange under the symbol "ENE PrR", and
186,000 Trust Common Securities (the "Trust Common Securities," and, together
with the Trust Preferred Securities, the "Trust Securities"), all of which are
owned by Enron Corp., a Delaware corporation ("Enron"). The Trust makes
distributions on the Trust Securities to the extent it receives distributions
from the Partnership on the Partnership Preferred Securities. Payments on the
Partnership Preferred Securities represent the sole source of revenue for the
Trust. Distributions on the Trust Securities are guaranteed by Enron, but only
to the extent that the Trust has available funds to pay such distributions. The
Trust was created for the sole purpose of issuing the Trust Securities,
investing the proceeds of such issuance in the Partnership Preferred Securities
and engaging in only those other activities necessary or incidental thereto. The
Trust Securities are subject to redemption at any time on or after March 31,
2002 and earlier in the event of certain tax law changes or other events.

         The general partner of the Partnership is Enron, which owns a 15%
general partnership interest in the Partnership. Since completion of the
offering of the Trust Preferred Securities on January 16, 1997, the assets of
the Partnership have been invested primarily in a $136,450,000 principal amount
7.75% Subordinated Debenture due 2016, Series II of Enron (the "Enron
Debenture") and $21,836,000 principal amount 7.75% Debentures due 2016, Series
II, of each of Enron Capital & Trade Resources Corp. and Enron Pipeline Company
(the "Subsidiary Debentures" and, together with the Enron Debenture, the
"Debentures"), each of which is a wholly owned subsidiary of Enron. The
obligations under the Subsidiary Debentures are guaranteed by Enron. The
respective issuers of the Debentures have certain rights to elect to defer any
payments of principal and interest on the Debentures for up to five years at a
time. In addition to the Debentures, the Partnership owns an aggregate of
approximately $1,851,000 in short-term, investment grade debt securities (the
"Eligible Debt Securities"). Under certain circumstances, upon repayment of one
or more of the Debentures, the assets of the Partnership may be reinvested in
one or more debt securities of Enron or its subsidiaries. Payments of interest
and principal on the Enron Debenture and the Subsidiary Debentures (or the
guarantees thereof) and the Eligible Debt Securities are the sole source of
revenue for the Partnership. The Partnership pays distributions to the Trust as
holder of the Partnership Preferred Securities when as and if Enron, as the
general partner, determines to do so, although Enron has no obligation to do so.

         For more information concerning the Trust, the Partnership and the
rights of the holders of the Trust Securities, see the Amended and Restated
Declaration of Trust relating to the Trust, the Amended and Restated Agreement
of Limited Partnership relating to the Partnership, the Indentures relating to

                                       2
<PAGE>   3

each of the Debentures and the Guarantee Agreements of Enron with respect to the
Trust Preferred Securities, the Partnership Preferred Securities and the
Subsidiary Debentures, each of which is included as an exhibit to this Form
10-K.

          Enron, a Delaware corporation organized in 1930, is an integrated
natural gas and electricity company headquartered in Houston, Texas. The common
stock of Enron is traded on the New York Stock Exchange under the symbol "ENE."
Essentially all of Enron's operations are conducted through its subsidiaries and
affiliates, which are principally engaged in the gathering, transportation and
wholesale marketing of natural gas to markets throughout the United States and
internationally through approximately 36,000 miles of natural gas pipelines; the
exploration for and production of natural gas and crude oil in the United States
and internationally; the production, purchase, transportation and worldwide
marketing of natural gas liquids and refined petroleum products; the independent
(i.e., non-utility) development, promotion, construction and operation of power
plants, natural gas liquids facilities and pipelines in the United States and
internationally; and the non-price regulated purchasing and marketing of
electricity and other energy related commitments.

      The location of the principal executive offices of the Trust and the
Partnership is c/o Enron Corp., 1400 Smith Street, Houston, Texas 77002, and its
phone number at such address is (713) 853-6161.

      NOTE: Because the Trust and the Partnership had no assets or liabilities
or operations as of December 31, 1996, and because the Trust and the Partnership
are special purpose financing entities with no separate business operations, the
only assets of the Trust are the Partnership Preferred Securities, and
substantially all of the assets of the Partnership consist of a debt security of
Enron and debt securities of subsidiaries of Enron that are guaranteed by Enron,
the Trust does not believe that financial statements for the Trust or the
Partnership are meaningful. Accordingly, financial statements and related
financial information have not been included in this Form 10-K. For further
information concerning Enron and its subsidiaries, including financial
statements and other financial information, see the Annual Report on Form 10-K
of Enron for the year ended December 31, 1996 as filed with the Securities and
Exchange Commission, a copy of which may be obtained from the corporate
secretary of Enron at the address listed on the cover of this Form 10-K.

ITEM 2.  PROPERTIES.

      Not applicable.

ITEM 3.  LEGAL PROCEEDINGS.

      None.

ITEM 4.  SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS.

      Not applicable.

                                       3
<PAGE>   4



                                     PART II

ITEM 5.  MARKET FOR THE REGISTRANT'S COMMON EQUITY AND RELATED STOCKHOLDER 
         MATTERS.

      The Trust Preferred Securities were issued on January 16, 1997 and have
been listed on the New York Stock Exchange ("NYSE") under the symbol "ENE PrR"
since that time. As of March 14, 1997, the approximate number of holders of
record of the Trust Preferred Securities was 66. All of the Trust Common
Securities are held by Enron.

      The Trust has declared its first scheduled regular quarterly distribution
on the Trust Securities of $.4232 per Trust Security payable to holders of
record on March 31, 1997, such initial distribution accruing from January 16,
1997, the date of original issuance of the Trust Securities. The Trust expects
to pay distributions on the Trust Securities of $.5078 per quarter to the extent
the Trust has funds available for the payment of such distributions.

      The Trust issued an aggregate of 186,000 Trust Common Securities to Enron
on January 16, 1997 in a transaction exempt from the Securities Act of 1933
pursuant to Section 4(2) thereof.

ITEM 6.  SELECTED FINANCIAL AND OPERATING DATA.

      See Note to Item 1.

ITEM 7.  MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND 
         RESULTS OF OPERATIONS.

      See Note to Item 1.

ITEM 8.  FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA.

      See Note to Item 1.

ITEM 9.  CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND 
         FINANCIAL DISCLOSURE.

          Not Applicable.

                                    PART III

ITEM 10.  DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT.

           The Trust is administered by five trustees (the "Trustees"). Three of
the Trustees, Keith A. Crane, Susan K. Hodge and Phillip M. Sisneros (the
"Regular Trustees") are employees of Enron or its subsidiaries. The fourth
trustee is The Chase Manhattan Bank, which is unaffiliated with Enron and acts
as indenture trustee for purposes of compliance with the provisions of the Trust
Indenture Act (the 

                                       4
<PAGE>   5

"Property Trustee"). The fifth trustee, Chase Manhattan Bank
Delaware, is also unaffiliated with Enron and serves as Delaware Trustee to
fulfill a requirement of the Trust Act.


ITEM 11.  EXECUTIVE COMPENSATION.

          The Regular Trustees are not compensated by the Trust or Enron for
their services as trustees. The Property Trustee and Delaware Trustee are not
compensated by the Trust but are paid customary compensation for their services
by Enron.

ITEM 12.  SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT.

          Not applicable.


ITEM 13.  CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS.

          Except as described above under Item 1, the Trust is not party to any
transactions with affiliates.

                                     PART IV

ITEM 14.  EXHIBITS, FINANCIAL STATEMENT SCHEDULES, AND REPORTS ON FORM 8-K.

          (a)(1) Financial Statements

          None.

          (a)(2) Financial Statement Schedules

          None.

          (a)(3) List of Exhibits

          4.1     Certificate of Trust  (incorporated  by reference to Exhibit 
                  4(a) of the  Registration  Statement on Form S-1 of the
                  Trust (No. 333-18669)).
          4.2     Amended and Restated Declaration of Trust dated as of 
                  January 13, 1997
          4.3     Amended and Restated  Agreement of Limited  Partnership of
                  the Enron  Preferred  Funding II, L.P. dated as of 
                  January 16, 1997
          4.4     Trust Preferred Guarantee Agreement dated as of 
                  January 16, 1997
          4.5     Partnership Preferred Guarantee Agreement dated as of 
                  January 16, 1997
          4.6     Indenture dated as of January 16, 1997 relating  to the  
                  Enron's 7.75% Subordinated Debentures due 2016, Series II
          4.7     Indenture  dated  as of  January  16,  1997  relating  to  
                  Enron  Pipeline  Company's  7.75% Debentures due 2016, 
                  Series II
          4.8     Indenture dated as of January 16, 1997 relating to the Enron
                  Capital & Trade Resources Corp. 7.75% Debentures due 2016,
                  Series II

                                       5
<PAGE>   6

          4.9     Guarantee  Agreement of Enron dated as of January 16, 1997
                  relating to Enron  Pipeline  Company's 7.75% Debentures due
                  2016, Series II
          4.10    Guarantee Agreement of Enron dated as of January 16, 1997 
                  relating to Enron Capital & Trade Resources Corp. 7.75% 
                  Debentures due 2016, Series II
          4.11    Form of certificate representing Trust Preferred Securities 
                  (included in Exhibit 4.2)
          27.1    Financial Data Schedule

         (b)  Reports on Form 8-K.

         No reports on Form 8-K have been filed during the last quarter of the
period covered by this report.

                                       6
<PAGE>   7

                                   SIGNATURES

         Pursuant to the requirements of the Securities Exchange Act of 1934,
the registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.



                                      ENRON CAPITAL TRUST II
                                      ----------------------
                                           (Registrant)



Date:  March 28, 1997                 By: /s/ Keith A. Crane
                                        ------------------------------
                                         Name:  Keith A. Crane
                                         Title: Regular Trustee



         Pursuant to the requirements of the Securities Exchange Act of 1934,
this Report has been signed below by the following persons on behalf of the
Registrant and in the capacities indicated as of March 28, 1997.

Name                                     Title
----                                     -----

  /s/ Keith A. Crane                     Regular Trustee
-----------------------------
Keith  A. Crane


   /s/  Susan K. Hodge                   Regular Trustee
-----------------------------
Susan K. Hodge


  /s/ Phillip M. Sisneros                Regular Trustee
-----------------------------
Phillip M. Sisneros


                                       7
<PAGE>   8

                                 EXHIBIT INDEX

          4.1     Certificate of Trust  (incorporated  by reference to Exhibit 
                  4(a) of the  Registration  Statement on Form S-1 of the
                  Trust (No. 333-18669)).
          4.2     Amended and Restated Declaration of Trust dated as of 
                  January 13, 1997
          4.3     Amended and Restated  Agreement of Limited  Partnership of
                  the Enron  Preferred  Funding II, L.P. dated as of 
                  January 16, 1997
          4.4     Trust Preferred Guarantee Agreement dated as of 
                  January 16, 1997
          4.5     Partnership Preferred Guarantee Agreement dated as of 
                  January 16, 1997
          4.6     Indenture dated as of January 16, 1997 relating  to the  
                  Enron's 7.75% Subordinated Debentures due 2016, Series II
          4.7     Indenture  dated  as of  January  16,  1997  relating  to  
                  Enron  Pipeline  Company's  7.75% Debentures due 2016, 
                  Series II
          4.8     Indenture dated as of January 16, 1997 relating to the Enron
                  Capital & Trade Resources Corp. 7.75% Debentures due 2016,
                  Series II
          4.9     Guarantee  Agreement of Enron dated as of January 16, 1997
                  relating to Enron  Pipeline  Company's 7.75% Debentures due
                  2016, Series II
          4.10    Guarantee Agreement of Enron dated as of January 16, 1997 
                  relating to Enron Capital & Trade Resources Corp. 7.75% 
                  Debentures due 2016, Series II
          4.11    Form of certificate representing Trust Preferred Securities 
                  (included in Exhibit 4.2)
          27.1    Financial Data Schedule