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                                                                    Exhibit 99.4

                                                                           PROXY
GIANT INDUSTRIES, INC.
23773 NORTH SCOTTSDALE ROAD, SCOTTSDALE AZ 85255


          THIS PROXY IS SOLICITED ON BEHALF OF THE BOARD OF DIRECTORS.

     The undersigned appoints James E. Acridge, Fredric L. Holliger, A. Wayne
Davenport and Morgan Gust, and each of them, as proxies, each with the power of
substitution, and authorizes them to represent and vote, as designated on the
reverse side hereof, all shares of Common Stock of Giant Industries, Inc. held
by the undersigned on May 21, 1998, at the Special Meeting of Stockholders to
be held on            , 1998, and at any adjournment or postponement of the
meeting. In their discretion, the proxies are authorized to vote such shares
upon such other business as may properly come before the Special Meeting.

     THIS PROXY, WHEN PROPERLY EXECUTED, WILL BE VOTED IN THE MANNER DIRECTED
BY THE UNDERSIGNED STOCKHOLDER(S). IF NO DIRECTION IS MADE, THIS PROXY WILL BE
VOTED FOR THE LISTED PROPOSALS.

Please mark boxes X in blue or black ink.

MERGER BETWEEN GIANT INDUSTRIES, INC. ("GIANT") AND HOLLY CORPORATION ("HOLLY"):

The Board of Directors unanimously recommends a vote FOR each of the proposals
listed below. You may vote on each proposal individually, or you may vote on
all proposals as a group as described below. More detailed information
concerning each of the proposals is provided in the Joint Proxy
Statement/Prospectus of Giant and Holly, dated           , 1998.

1. Approval of Proposals 2, 3, 4, and 5 below relating to the merger (the
   "Merger") of Holly with and into Giant (a vote "for" or "against" or an
   "abstain" on this Proposal 1 is a vote "for" or "against" or an "abstain" on
   each of the Proposals 2, 3, 4, and 5 below).

   / / FOR    / / AGAINST    / / ABSTAIN

                   IF YOU MARKED ANY BOX ON PROPOSAL 1 ABOVE
              DO NOT MARK ANY BOX ON PROPOSALS 2, 3, 4 OR 5 BELOW.
                                        
  If you marked any box on Proposal 1 above and also mark any box on Proposals
  2, 3, 4 or 5 below, your vote on Proposal 2, 3, 4 or 5 below will, to the
  extent inconsistent with your vote on Proposal 1, take precedence over your
  vote on Proposal 1.

2. Approval of the Merger, the Merger Agreement and the transactions
   contemplated thereby.

   / / FOR    / / AGAINST    / / ABSTAIN

3. Approval of the proposal to amend and restate Giant's certificate of
   incorporation in its entirety.

   / / FOR    / / AGAINST    / / ABSTAIN

4. Approval of the proposal to amend and restate Giant's bylaws in their
   entirety.

   / / FOR    / / AGAINST    / / ABSTAIN

5. Approval of the proposal to issue authorized but unissued Common Stock of
   Giant in accordance with the terms of the Merger Agreement.

   / / FOR    / / AGAINST    / / ABSTAIN

GIANT 1998 STOCK INCENTIVE PLAN:

The Board of Directors unanimously recommends a vote FOR the proposal listed
below. More detailed information concerning the proposal is provided in the
Joint Proxy Statement/Prospectus of Giant and Holly, dated           , 1998.

6. Approval of the proposal to adopt the Giant 1998 Stock Incentive Plan.

   / / FOR    / / AGAINST    / / ABSTAIN