Oil and gas interests poured more than half-a-million dollars into the last campaigns of nine Senate Finance Committee members who are involved in developing energy legislation, according to Congress Watch, a lobbing organization.

Six of the nine senators are members of the House-Senate conference committee that is attempting to agree on energy-tax legislation that will directly affect oil and gas industry profits.

Congress Watch, an arm of Ralph Nader's Public Citizen group, reported in a study released yesterday that more than $547,000 was given by the industry to the nine committee members in election campaigns in 1974, 1975 and 1976.

Almost half the total - $265,181 - went to Sen. Lolyd Bentsen (D-Tex.), who is one of the energy conferees.

Mark Green, director of Congress Watch, said the study, drawn from public financing reports, shows "the potential for a tilt toward industry when difficult policy decisions are being made."

Green said the data "provides an eloquent argument for the public funding, rather than the corporate funding, of public elections."

"The point is that the system permits businesses to make contributions - it is a form of corporate funding." Green said. "It also permits an already-cynical public to view these contributions as an 'investment' being made by industry."

In addition to the $265,181 listed in records of Bentsen, a supporter of the industry who led the fight for deregulation of natural gas prices in the Senate, Congress Watch came up with these other figures:

Sens. Bob Dole (R-Kan.) received $85,577; Mike Gravel (D-Alaska), $84,189; Russell Long (D-La.), the committee chairman, $55,495, $55,498; John Danforth (R-Mo.), $21,025; William Roth (R-Del.), $16,179; Paul Laxalt (R-Nev.), $7,000; Harry Byrd (Ind-Va.), $7,000; Spark Matsunaga (D-Hawaii), $6,571.

In compiling its study, Congress Watch included contributions from oil producers, drillers, contractors, company executives and political-action committees, as well as attorneys whose firms represent oil and gas interests.

Bentsen was not availabe for comment yesterday, but his press aide, Jack DeVore, challenged the accuracy of the Congress Watch figures and denied any connection between contributions and Bentsen's attitude.

DeVore said that Congress Watch had included in its compilation contributions made in 1974 to Bentsen's short-lived presidential campaign - a point which he said distorted the findings. Bentsen was re-elected to the Senate last year.

"Their report is not accurate and I think that makes a difference. There is no quid pro quo - in a state like Texas, where oil and gas are an important part of the economy, you expect to see contributions like this," he said.