SECURITIES AND EXCHANGE COMMISSION
                                WASHINGTON, D.C.

                                    FORM 8-A


               FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES
                    PURSUANT TO SECTION 12(b) OR (g) OF THE
                        SECURITIES EXCHANGE ACT OF 1934


                      FIRST TRUST EXCHANGE-TRADED FUND IV
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             (Exact name of registrant as specified in its charter)


              MASSACHUSETTS                            See Exhibit 1
----------------------------------------   -------------------------------------
(State of Incorporation or Organization)   (I.R.S. Employer Identification No.)


120 East Liberty Drive, Suite 400, Wheaton, Illinois              60187
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      (Address of Principal Executive Offices)                 (Zip Code)


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

         TITLE OF EACH CLASS                  NAME OF EACH EXCHANGE ON WHICH
         TO BE SO REGISTERED                  EACH CLASS IS TO BE REGISTERED

Common Shares of Beneficial Interest,           The NASDAQ Stock Market LLC
      $.01 par value per share,
                  of
  First Trust Low Duration Mortgage
          Opportunities ETF


If this form relates to the registration of a class of securities pursuant to
Section 12(b) of the Exchange Act and is effective pursuant to General
Instruction A. (c), check the following box.--
[X]


If this form relates to the registration of a class of securities pursuant to
Section 12(g) of the Exchange Act and is effective pursuant to General
Instruction A. (d), check the following box.--
[  ]


Securities Act registration statement file number to which this form relates:
333-174332.





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

                                      None
--------------------------------------------------------------------------------
                          TITLE OF EACH CLASS TO BE REGISTERED



                 INFORMATION REQUIRED IN REGISTRATION STATEMENT

ITEM 1.    DESCRIPTION OF REGISTRANT'S SECURITIES TO BE REGISTERED

      The securities to be registered hereunder are common shares of beneficial
interest, $.01 par value per share (the "Shares"), of the First Trust Low
Duration Mortgage Opportunities ETF (the "Fund"), a series of the First Trust
Exchange-Traded Fund IV (the "Registrant"). An application for listing of the
Shares of the Fund has been filed with and approved by The NASDAQ Stock Market
LLC. A description of the Shares is contained in the Prospectus, which is a part
of the Registration Statement on Form N-1A (Registration Nos. 333-174332 and
811-22559), filed with the Securities and Exchange Commission on October 10,
2014. Such description is incorporated by reference herein.

ITEM 2.    EXHIBITS

      Pursuant to the "Instruction as to Exhibits" of Form 8-A, no exhibits are
filed herewith or incorporated by reference.





                                   SIGNATURE

      Pursuant to the requirements of Section 12 of the Securities Exchange Act
of 1934, the Registrant has duly caused this registration statement to be signed
on its behalf by the undersigned, thereto duly authorized.

                                             FIRST TRUST EXCHANGE-TRADED FUND IV



                                             By: /s/ W. Scott Jardine
                                                 -------------------------------
                                                 W. Scott Jardine, Secretary

November 3, 2014





                                   Exhibit 1

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                                                           I.R.S. EMPLOYER
                        FUND                              IDENTIFICATION NO.
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First Trust Low Duration Mortgage Opportunities ETF           32-0441405
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