<PAGE>
                                                                    EXHIBIT 14.1

                             GIANT INDUSTRIES, INC.
                       CODE OF BUSINESS CONDUCT AND ETHICS
                           FOR DIRECTORS AND EMPLOYEES
                             ADOPTED MARCH 11, 2004

INTRODUCTION

This Code of Business Conduct and Ethics (the "Code") covers a wide range of
business practices and procedures. It does not cover every issue that may arise,
but it sets out basic principles to guide all directors of Giant Industries,
Inc. and its subsidiaries (collectively, the "Company") and all employees,
including officers, of the Company. All of our employees and directors must
conduct themselves in accordance with the Code and seek to avoid the appearance
of improper behavior.

If a law or regulation conflicts with a policy in this code, you must comply
with the law; however, if a local custom or policy conflicts with this Code, you
must comply with the Code. QUESTIONS SHOULD BE REFERRED TO THE EMPLOYEE'S
SUPERVISOR OR TO THE COMPANY'S LEGAL DEPARTMENT BEFORE ACTION IS TAKEN IF YOU
ARE UNSURE WHAT TO DO.

Those who violate the standards in this Code will be subject to disciplinary
action, up to and including termination. If you are in a situation that you
believe may violate or lead to a violation of this Code, follow the guidelines
described in Sections 11 and 12 of this Code.

1.    COMPLIANCE WITH LAWS, RULES AND REGULATIONS

      Doing what is right, treating others as you would want to be treated, and
obeying the law, both in letter and in spirit, are the foundations on which this
Company's ethical standards are built. We expect all of our employees and
directors to endeavor to respect and obey the applicable laws of the relevant
jurisdictions in which we operate. Although not all employees and directors are
expected to know the details of these laws, it is important to know enough to
determine when to seek advice from supervisors, managers or the Company's Legal
Department.

2.    CONFLICTS OF INTEREST

      A "conflict of interest" exists when a person's private interest
interferes in any way - or appears to interfere - with the interests of the
Company. A conflict situation can arise when an employee or director takes
actions or has interests that may make it difficult to perform his or her
Company work objectively and effectively. Conflicts of interests also may arise
when an employee or director, or members of his or her family, receives improper
personal benefits as a result of his or her position in the Company.

      It is almost always a conflict of interest for a Company employee to work
simultaneously for a competitor, customer or supplier. Employees are not allowed
to work for a competitor as an employee, consultant or board member. The best
policy is to avoid any direct or indirect business connection with our
customers, suppliers or competitors, except on the Company's behalf.

      Directors should inform the Chair of the Corporate Governance and
Nominating Committee and the CEO prior to accepting appointments to the board of
directors or the advisory board of any public or privately held company. The
disclosure requirements and other possible conflict of interest issues involved
must be analyzed and discussed.


                                       1
<PAGE>
      Except as approved in advance by the Board of Directors (the "Board"), or
as otherwise specified by the Board, conflicts of interest are prohibited as a
matter of Company policy. Conflicts of interest may not always be clear cut, so
if an employee or a director has a question, he or she should consult with
higher levels of management or the Company's Legal Department. Any employee or
director who becomes aware of a conflict or potential conflict should bring it
to the attention of a supervisor, manager or other appropriate personnel or
consult the procedures described in Section 12 of this Code.

3.    INSIDER TRADING

      As more particularly described in the Company's Personnel Reference Manual
and the Company's Policies and Procedures, employees and directors who have
access to confidential information are not permitted to use or share that
information for stock trading purposes or for any other purpose except the
conduct of our business. All non-public information about the Company and its
business relationships should be considered confidential information. To use
non-public information for personal financial benefit or to "tip" others who
might make an investment decision on the basis of this information is not only
unethical but also illegal. If you have any questions, please consult the
Company's Legal Department.

4.    CORPORATE OPPORTUNITIES

      Employees and directors are prohibited from taking for themselves
personally, or for members of their family, opportunities that are discovered
through the use of corporate property, information or position without the
consent of the Board. No employee or director may use corporate property,
information, or position for improper personal gain, and no employee may compete
with the Company directly or indirectly. Employees and directors owe a duty to
the Company to advance its legitimate interests when the opportunity to do so
arises.

5.    COMPETITION AND FAIR DEALING

      We seek to outperform our competition fairly and honestly. We seek
competitive advantages through superior performance, never through illegal
business practices. Stealing, or inducing others to steal, proprietary
information of other companies is prohibited. Each employee should endeavor to
respect the rights of and deal fairly with the Company's customers, suppliers,
and employees.

      To maintain the Company's valuable reputation, compliance with our quality
processes and safety requirements is essential. In the context of ethics, our
products should be designed and manufactured, and our services should be
performed, to meet our obligations to customers. All inspection and testing
documents must be handled in accordance with all applicable regulations.

      The purpose of business entertainment and gifts in a commercial setting is
to create good will and sound working relationships. No gift or entertainment
should ever be offered, given, provided or accepted by any Company employee,
director, agent, or family member thereof, unless it: (i) is not a cash gift;
(ii) is consistent with customary business practices; (iii) cannot be construed
as a bribe or payoff and (iv) does not violate any laws or regulations or the
Gift Policy set forth in the Company's Personnel Reference Manual. Employees
should discuss with their supervisors or the Company's Legal Department and
directors should discuss with the Company's Legal Department, any gifts or
proposed gifts that they are not certain are appropriate.


                                       2
<PAGE>
6.    DISCRIMINATION AND HARASSMENT

      We are firmly committed to providing equal opportunity in all aspects of
employment and, as more particularly described in the Company's Personnel
Reference Manual, we will not tolerate any illegal discrimination or harassment
of any kind.

7.    HEALTH AND SAFETY

      As more particularly described in the Company's Personnel Reference
Manual, the Company strives to provide each employee with a safe and healthy
work environment. Each employee has responsibility for maintaining a safe and
healthy workplace for all employees by following safety and health rules and
practices and reporting accidents, injuries and unsafe equipment, practices or
conditions.

      As more particularly described in the Company's Personnel Reference
Manual, employees should report to work in condition to perform their duties,
free from the influence of illegal drugs or alcohol.

8.    RECORD-KEEPING

      The Company requires honest and accurate recording and reporting of
information in order to make responsible business decisions. For example, only
the true and actual number of hours worked should be reported.

      Many employees regularly use business expense accounts, which must be
documented and recorded accurately. If you are not sure whether a certain
expense is appropriate, ask your supervisor or the Accounting Department. Rules
and guidelines are set forth in the Company's Policies and Procedures and are
available from the Accounting Department. All of the Company's books, records,
accounts and financial statements should be maintained in reasonable detail,
should appropriately reflect the Company's transactions, and should conform to
currently applicable legal requirements, generally accepted accounting
principles (GAAP), and the Company's system of internal controls.

      Business records and communications often become public, and we should
avoid exaggeration, derogatory remarks, guesswork, or inappropriate
characterizations of people and companies that can be misunderstood. This
applies equally to e-mail, internal memos, and formal reports. Records should be
retained or destroyed according to the Company's record retention policy set
forth in the Company's Policies and Procedures. In accordance with those
policies, in the event of litigation or governmental investigation please
consult the Company's Legal Department.

9.    CONFIDENTIALITY

      As more particularly described in the Company's Personnel Reference Manual
and the Company's Policies and Procedures, employees and directors must maintain
the confidentiality of confidential information entrusted to them by the
Company, its advisors, or its customers, except when disclosure is authorized by
the Legal Department or required by laws or regulations. Confidential
information includes all non-public information that might be of use to
competitors, or harmful or embarrassing to the Company or its customers, if
disclosed. It also includes information that suppliers and customers have
entrusted to us. The obligation to preserve confidential information continues
even after employment or directorship terminates.


                                       3
<PAGE>
10.   PROTECTION AND PROPER USE OF COMPANY ASSETS

      Employees and directors should endeavor to protect the Company's assets
and ensure their efficient use. Theft, carelessness, and waste have a direct
impact on the Company's profitability. Any suspected incident of fraud or theft
should be immediately reported for investigation. Company equipment should not
be used for non-Company business, though incidental personal use may be
permitted.

      The obligation of employees and directors to protect the Company's assets
includes its proprietary information. Proprietary information includes
intellectual property such as trade secrets, patents, trademarks, and
copyrights, as well as business, marketing and service plans, engineering and
manufacturing ideas, designs, databases, records, salary information and any
unpublished financial data and reports. Unauthorized use or distribution of this
information violates Company policy. It could also be illegal and result in
civil or even criminal penalties.

11.   REPORTING ANY ILLEGAL OR UNETHICAL BEHAVIOR

      Employees and directors are encouraged to talk to supervisors, managers,
the Company's Legal Department or other appropriate personnel about observed
illegal or unethical behavior and, when in doubt, about the best course of
action in a particular situation. It is the policy of the Company not to allow
retaliation for reports of misconduct by others made in good faith by employees.
Employees are expected to cooperate in internal investigations of misconduct.

12.   COMPLIANCE PROCEDURES

      We must all work to ensure prompt and consistent action against violations
of this Code. In some situations, however, it is difficult to know right from
wrong. Since we cannot anticipate every situation that will arise, it is
important that we have a way to approach a new question or problem. These are
the steps directors and employees should keep in mind:

      -     Make sure you have all the facts. In order to reach the right
            solutions, we must be as fully informed as possible.

      -     Ask yourself: What specifically am I being asked to do? Does it seem
            illegal or improper? This will enable you to focus on the specific
            question you are faced with, and the alternatives you have. Use your
            judgment and common sense.

      -     Clarify your responsibility and role. In many situations, there is
            shared responsibility. Are your colleagues informed? It may help to
            get others involved and discuss the problem.

      -     Discuss the problem with your supervisor. This is the basic guidance
            for all situations. In many cases, your supervisor will be more
            knowledgeable about the question, and will appreciate being brought
            into the decision-making process. Remember that it is your
            supervisor's responsibility to help solve problems.

      -     Seek help from Company resources. In a case where it may not be
            appropriate to discuss an issue with your supervisor, or where you
            do not feel comfortable approaching your supervisor with your
            question, discuss it locally with your office manager or your Human
            Resources manager. If that also is not appropriate, call
            800-937-4937, Ext. 8797, the Company's toll-free Business Practices
            Hot Line.


                                       4
<PAGE>
      -     Report ethical violations in confidence and without fear of
            retaliation. You are encouraged to report ethical violations. If
            your situation requires that your identity be kept secret, your
            anonymity will be protected to the extent permitted by law. The
            Company does not permit retaliation against employees for good faith
            reports of ethical violations.

      -     Always ask first, act later. If you are unsure of what to do in any
            situation, seek guidance before you act.

13.   PROVISIONS APPLICABLE TO THE PRINCIPAL EXECUTIVE OFFICER AND TO THE SENIOR
      FINANCIAL OFFICERS

      The Company's principal executive officer, principal financial officer,
principal accounting officer, controller, and other persons performing similar
functions (collectively, the "Financial Officers") are responsible for full,
fair, accurate, timely and understandable disclosure in the periodic reports
required to be filed by the Company with the Securities and Exchange Commission.
As a result, the Financial Officers of the Company are subject to the following
specific provisions:

      -     The Financial Officers shall promptly bring to the attention of the
            Company's Disclosure Committee any material information of which he
            or she may become aware that could affect the disclosures made by
            the Company in its public filings or otherwise assist management in
            fulfilling its responsibilities.

      -     The Financial Officers shall promptly bring to the attention of the
            Company's Disclosure Committee and the Audit Committee any
            information he or she may have concerning: (i) significant
            deficiencies in the design or operation of internal controls which
            could adversely affect the Company's ability to record, process,
            summarize and report financial data; or (ii) any fraud, whether or
            not material, that involves management or other employees who have a
            significant role in the Company's financial reporting, disclosures
            or internal controls.

      -     The Financial Officers shall promptly bring to the attention of the
            General Counsel and the Audit Committee any information he or she
            may have concerning any material violation of this Code by any
            management or other employees who have a significant role in the
            Company's financial reporting, disclosures or internal controls.

      -     The Financial Officers shall promptly bring to the attention of the
            General Counsel, the Audit Committee and the Chief Executive Officer
            (the "CEO") any information he or she may have concerning evidence
            of a material violation of the securities or other laws, rules or
            regulations applicable to the Company and the operation of its
            business, by the Company or any agent thereof, or of violation of
            this Code.

      -     The Financial Officers shall promptly bring to the attention of the
            General Counsel, the Audit Committee and the CEO (unless the CEO is
            a party to the transaction or the relationship) any material
            transaction or relationship that arises and of which he or she
            becomes aware that reasonably could be expected to give rise to an
            actual or apparent conflict of interest.

14.   WAIVERS OF THE CODE OF BUSINESS CONDUCT AND ETHICS

      Every effort will be made to resolve potential conflicts of interest or
other situations involving potential violations of this Code when they are
disclosed promptly to management and the parties involved have acted in good
faith. In the unlikely event potential conflicts cannot be resolved, waivers


                                       5
<PAGE>
will only be given for matters where it is appropriate under the circumstances
and the granting of such a waiver will not present a material financial or
reputational risk to the Company. All such waivers must be approved, in advance,
by the Board or as otherwise specified by the Board.

15.   EMPLOYEE COMPLAINT PROCEDURES

      Any employee of the Company may submit a good faith complaint regarding
the business practices of the Company to the management of the Company without
fear of dismissal or retaliation. The Company is committed to achieving
compliance with all applicable laws and regulations, accounting standards,
accounting controls and audit practices. The Company's Audit Committee will
oversee treatment of employee concerns in this area.

      In order to facilitate the reporting of employee complaints, the Company's
Audit Committee has established the following procedures for: (i) the receipt,
retention and treatment of complaints regarding accounting, internal accounting
controls, or auditing matters ("Accounting Matters"); (ii) the confidential,
anonymous submission by employees of concerns regarding questionable accounting
or auditing matters; and (iii) the receipt, retention, and treatment of
complaints or concerns regarding any other business practices of the Company.

Receipt of Employee Complaints

-     Employees may forward complaints on a confidential or anonymous basis to
      the following:

                             Giant Industries, Inc.
                           Business Practices Hotline
                             800-937-4937, Ext. 8797

-     Employees with concerns also may report their concerns directly to the
      Company's General Counsel.

Treatment of Complaints

-     All messages received on the Business Practices Hotline will be logged
      into a record kept by the Legal Department and will be initially referred
      to the Company's General Counsel (the "GC") and Chief Accounting Officer
      (the "CAO"). Messages involving material dollar amounts and/or executive
      officers of the Company also will immediately be referred to the Chairman
      of the Company's Audit Committee and the Company's CEO.

-     The Audit Committee will coordinate the investigation of all messages
      involving material dollar amounts and/or executive officers of the
      Company. The GC and the CAO will coordinate the investigation of all other
      messages received. The Audit Committee, GC and CAO may delegate tasks to
      any Company employee or independent third party they deem appropriate.
      They also will regularly report to the CEO and the President on the status
      and/or outcome of the investigations of each matter; provided that,
      matters involving either the CEO or the President of the Company will be
      reported to the full Board.

-     A written record of the course of each investigation and the outcome will
      be created and maintained in the Legal Department or by an independent
      third party if so directed by the Audit Committee.


                                       6
<PAGE>
-     At each regularly scheduled meeting of the Company's Audit Committee and
      at any other time requested by the Audit Committee or the Board, the GC
      and/or CAO will give a report on all the messages received and the status
      and/or outcome of the investigations of each matter.

-     The Company will not discharge, demote, suspend, threaten, harass or in
      any manner discriminate against any employee in the terms and conditions
      of employment based upon any lawful actions of such employee with respect
      to good faith reporting of complaints regarding accounting matters or
      otherwise as specified in Section 806 of the Sarbanes-Oxley Act of 2002.


                                       7