Exhibit 5.1

                                August 28, 2000

Quantum Corporation
500 McCarthy Boulevard
Milpitas, CA 95035

     RE:  REGISTRATION STATEMENT ON FORM S-8

Ladies and Gentlemen:

     We have examined the Registration Statement on Form S-8 to be filed by you
with the Securities and Exchange Commission on or about August 28, 2000 (the
"Registration Statement"), in connection with the registration under the
Securities Act of 1933, as amended, of 5,750,000 shares of Quantum Corporation--
HDDG Common Stock, par value $.01 per share, and 9,750,000 shares of Quantum
Corporation--DSSG Common Stock, par value $0.01 per share (the "Shares"),
reserved for issuance pursuant to the Supplemental  Stock Option Plan (the
"Plan").  As your counsel in connection with the transaction, we have examined
the proceedings taken and are familiar with the proceedings proposed to be taken
by you in connection with the sale and issuance of the Shares pursuant to the
Plan.

     It is our opinion, when issued and sold in the manner referred to in the
Plan, the Shares will be legally and validly issued, fully paid and
nonassessable.

     We consent to the use of this opinion as an exhibit to the Registration
Statement and further consent to the use of our name wherever appearing in the
Registration Statement and any amendment thereto.

                                    Very truly yours,

                                    WILSON SONSINI GOODRICH & ROSATI
                                    Professional Corporation

                                    /s/ Wilson Sonsini Goodrich & Rosati