EX-8.1

EXHIBIT 8.1



[FENWICK & WEST LLP LETTERHEAD]



May 3, 2000



MARVELL TECHNOLOGY GROUP LTD.
Clarendon House
2 Church Street
Hamilton, HMCX
Bermuda

Attention: Board of Directors

Re: Tax Opinion for the Initial Public Offering of Marvell Technology Group
Ltd.

Ladies and Gentlemen:

We have been requested to render an opinion concerning the matters of
United States federal income tax law in connection with the initial public
offering of Marvell Technology Group Ltd. ("Marvell").

It is our opinion that the section of the Form S-1 entitled "Taxation of
Shareholders -- United States Federal Income Tax Considerations" summarizes the
material United States federal income tax considerations that apply to the
ownership and disposition of Marvell common stock held by prospective United
States Holders, as that term is defined therein, as of the date of the Form S-1.

You should be aware that an opinion of counsel represents only counsel's
best legal judgment, and has no binding effect or official status of any kind,
and that no assurance can be given that contrary positions may not be taken by
the Internal Revenue Service or that a court considering the issues would not
hold otherwise. We undertake no responsibility to advise you of any subsequent
developments in the application, operation or interpretation of the United
States federal income tax laws.

This opinion is being delivered solely for use in connection with the
initial public offering of Marvell. This opinion may not otherwise be relied
upon or utilized for any other purpose or by any other person or entity, and may
not be made available to any other person or entity, without our prior written
consent.

Very truly yours,

/s/ FENWICK & WEST LLP
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