Minerals Management Service Improvement Act of 2008

Minerals Management Service Improvement Act of 2008 - Prohibits any employee of the Minerals Management Service of the Department of the Interior from: (1) knowingly accepting a gift from an entity engaged in the business of mineral mining or from being employed by such an entity while employed in the Service; and (2) accepting employment from an entity engaged in the business of mineral mining during the one-year period after termination of employment with the Service. Makes violations of such prohibitions a felony. Requires financial disclosure by employees of the Service in positions equivalent to GS-13 or higher.

Suspends the authority of the Secretary of the Interior to carry out royalty-in-kind programs (payment of royalties from oil and gas leases in the form of production rather than cash) until the Secretary certifies that a comprehensive review of such programs has been conducted, implements an ethics training program for employees of the Minerals Management Service, and creates an ombudsman position to monitor the progress of the Service in carrying out reforms. Requires the Secretary to perform at least 550 audits in each fiscal year of oil and gas leases for which payment is made under a royalty-in-kind program.

Amends the Energy Policy Act of 2005 to repeal the authority of the Secretary to pay salaries and other administrative costs related to a royalty-in kind program from royalty-in-kind sales revenues.