EXHIBIT 5.1

                      [LETTERHEAD OF IRELL & MANELLA LLP]

                                April 16, 1999
 
Mattel, Inc.
333 Continental Boulevard
El Segundo, California 90245-5012


     Re:     Series D Medium-Term Notes
             --------------------------

Ladies and Gentlemen:

     We have acted as counsel for Mattel, Inc., a Delaware corporation (the
"Company"), in connection with the Company's Registration Statement on Form S-3
(No. 333-68017)(the "Registration Statement"), with respect to the registration
under the Securities Act of 1933, as amended (the "Act"), of up to $400,000,000
(or the equivalent thereof in one or more foreign currencies or composite
currencies) aggregate initial offering price of an indeterminate amount of
various Securities (as defined in the Registration Statement).  The
Registration Statement was initially filed with the Securities and Exchange
Commission (the "Commission") on November 25, 1998, and was declared effective
by the Commission on December 8, 1998, having the effect of qualifying the
indenture dated as of February 15, 1996 (the "Indenture") between the Company
and Chase Manhattan Bank and Trust Company, N.A. (formerly Chemical Trust
Company of California), as trustee (the "Trustee"), under the Trust Indenture
Act of 1939, as amended (the "Trust Indenture Act").  Pursuant to the Indenture,
the Company proposes to issue up to $400,000,000 (or the equivalent thereof in
one or more foreign currencies or composite currencies) in aggregate principal
amount of Securities designated as Series D Medium-Term Notes (the "Notes").
The Notes will be offered on a continuing basis pursuant to Rule 415 under the
Act by the Prospectus dated April 16, 1999 (the "Basic Prospectus"), as
supplemented by the Prospectus Supplement dated April 16, 1999 (the "Supplement"
and, together with the Basic Prospectus, the "Prospectus").  The Prospectus will
be further supplemented by pricing supplements, each of which will be dated
approximately as of the date of sale of particular Notes and will furnish
information as to the specific terms thereof.

     For purposes of this opinion, we have reviewed such corporate records,
agreements and other instruments, and certificates of public officials, and have
considered such questions of law, as we deemed necessary or appropriate for the
purposes of this opinion.

 
Mattel, Inc.
April 16, 1999
Page 2

     On the basis of the foregoing and in reliance thereon, we are of the
opinion that the issuance and sale of Notes have been duly authorized and, when
the final terms of a particular Note and of its issuance and sale have been duly
established in accordance with the provisions of the Indenture and when the
Notes have been executed and authenticated in accordance with the provisions of
the Indenture and delivered to and paid for by the purchasers thereof in the
manner provided in the Distribution Agreement dated April 16, 1999 between the
Company and, as Agents, Morgan Stanley & Co. Incorporated and Credit Suisse
First Boston Corporation, the Notes will be entitled to the benefits of the
Indenture and will be valid and binding obligations of the Company, enforceable
in accordance with their respective terms.

     With respect to the opinions rendered above relating to enforceability of
the Notes:

     (i) such opinions are subject to the following exceptions, limitations and
qualifications: (a) the effect of bankruptcy, insolvency and similar laws
affecting creditors' rights generally; (b) the effect of general principles of
equity, including, without limitation, concepts of materiality, reasonableness,
good faith and fair dealing and the possible unavailability of specific
performance or injunctive relief, regardless of whether such enforceability is
considered in a proceeding in equity or at law; and (c) certain rights, remedies
and waivers contained in the Indenture or the Notes may be limited or rendered
ineffective by applicable California laws or judicial decisions governing such
provisions, but such laws or judicial decisions do not render the Indenture or
the Notes invalid or unenforceable as a whole;

     (ii) we express no opinion with respect to (a) the enforceability of the
waiver of rights or defenses contained in Section 4.4 of the Indenture or (b)
whether acceleration of any Notes that may have been sold for less than the full
face amount thereof may affect the collectibility of that portion of the stated
principal amount thereof that might be determined to constitute unearned
interest thereon; and

     (iii) in rendering such opinions, we have assumed that the interest rates
on the Notes at the time of their determination will not exceed the maximum rate
permitted under the usury laws of the State of California.

             To the extent the obligations of the Company under the Indenture
and with respect to the Notes may be dependent upon such matters, we assume for
purposes of the opinions rendered above that the Trustee has complied with any
applicable requirement to file returns and pay taxes under the Franchise Tax Law
of the State of California; that the Trustee is duly organized, validly existing
and in good standing under the laws of its jurisdiction of organization; that
the Trustee is duly qualified to engage in the activities contemplated by the
Indenture; that the Indenture has been duly authorized, executed and delivered
by the Trustee and constitutes the valid and binding obligation of the Trustee
enforceable against the Trustee in accordance with its terms; that, with respect
to acting as a 

 
Mattel, Inc.
April 16, 1999
Page 3

trustee under the Indenture, the Trustee is generally in compliance with all
applicable laws and regulations; and that the Trustee has the requisite
organizational and legal power and authority to perform its obligations under
the Indenture.

  Please be advised that we are licensed to practice law only in the State of
California.  We express no opinion as to the law of any jurisdiction other than
the laws of the State of California, the Delaware General Corporation Law and
the United States federal laws.

  This opinion is being rendered as of the date hereof and we assume no
obligations whatsoever to modify or update this opinion subsequent to the date
hereof, or to correct this opinion to the extent it may be rendered inaccurate
as a result of facts, circumstances or laws not in existence on the date hereof.

  This opinion is rendered solely for your benefit in connection with the
transactions described above.  We hereby consent to the use of this opinion as
an exhibit to the Company's Current Report on Form 8-K, event date April 16,
1999.  In giving such consent, we do not thereby admit that we are in the
category of persons whose consent is required under Section 7 of the Act.


                              Very truly yours,



                              /s/ Irell & Manella LLP
                                  Irell & Manella LLP