U.S. District Judge June L. Green ruled yesterday that she had no jurisdiction in a small-business case challenging the Department of Interior's decision to increase costs for oil and gas lease fees and rents.

The Interior Department had contended that the judge had no jurisdiction in the case brought under the Regulatory Flexibility Act because the act specifically precludes judicial review of agencies' decisions. It was the first case brought under the recently enacted law that, among other things, requires agencies to determine the impact of particular decisions on small businesses.

The case was brought by Stephen Thompson, owner of a small, Dallas-based oil and gas drilling firm. Thompson claimed in his suit that the Interior Department didn't follow the act and that the agency's action would reduce the projected number of lease applications in fiscal 1982 from between 4 million and 5 million to between 2 million and 3 million.

In addition, he claimed that the increase in the cost of renting a lease after five years of the lease's term would cause as many as half of the firms to relinquish their leases.

Charles A. Price, Thompson's attorney, said last night he didn't know whether his client would appeal Green's decision to the U.S. Circuit Court of Appeals for the District of Columbia.

The case has aroused the concern of several congressmen, who said they may investigate why the Small Business Administration's advocacy office did not file a friend of the court brief in the case on the side of the small-business person. The SBA had considered filing such a brief but declined at the last minute.