Practically the first statement made by George A. Keyworth Jr. when he was named to head the White House Office of Science and Technology Policy was that he would not act as a lobbyist for the science community inside the White House.

When President Reagan's first budget hacked large holes in the federal basic science budget, scientists were quickly convinced that Keyworth meant what he said.

"The research community got the heebie-jeebies scared out of them at the beginning of the Reagan administration," said Dennis Barnes, chief scientist for the Senate Committee on Commerce, Science and Transportation. "They were afraid they'd get dumped on."

So squads of scientists began coming to Washington for emergency meetings. Sessions were arranged at the old forts of establishment science, the National Academy of Sciences and the American Association for the Advancement of Science. A blizzard of letters hit Capitol Hill and the federal agencies, along with a gale of telephone calls and a hailstorm of door-knocking.

Some of the sudden fear that struck in the budget emergencies of 1981 eventually froze in place. The result: there are now half a dozen new science lobbying or "information" organizations in Washington, among them the Coalition for Social Science Associations, the National Coalition for Science and Technology, a Washington office for the American Physical Society and the Space Science Working Group.

Since all this activity began, the sciences have been more successful in getting their budget desires. Whether that is the result of the new fever of activity from scientists or should be attributed instead to a change in attitude in the administration is not clear. But the budget numbers for basic science have bounced back up, even though not quite to their pre-Reagan levels.

The federal science agencies view the new lobbies with mixed feelings. Keyworth rejects the notion that scientists or their lobbies may have played a part in gaining some of the big increases in the 1984 budget requests for science. The increases, as high as 25 percent in some major parts of the National Science Foundation, "cannot be attributed to political pressure," he has been quoted as saying.

Keyworth said at his 1984 budget briefing that in practically every conversation with the president or Cabinet about how to revive industry or strengthen defense, the answer was the same: strengthen science. So the budget for physics, mathematics, engineering and related fields have gone up sharply.

But congressional staffers say that the new effort by scientists must have had some impact on the White House, and has certainly had an impact on Congress, where the letters have poured in during orchestrated campaigns.

A spokesman for Keyworth's office said the office has little or no contact with the new science lobbies, though it maintains contacts with the main-line science groups.

But below the White House level, agencies are not so stand-offish. Tom Ubois, the National Science Foundation's assistant director for administration, said NSF officials have had a number of meetings with the Coalition for Social Science Associations.

In order to become more of a force in Washington, scientists have had to begin to shed their traditional reluctance to get involved in politics.

Scientists now "perceive that decisions are being made today not on objective grounds or on scientific grounds, but basically are being made on a political basis. So they are saying, 'If that is that way things are, we will have to participate in politics,' " said Marc Rosenberg, head of the Washington office of the National Coalition for Science and Technology, the newest science lobby in Washington.

The science lobbies are expected to be getting a lot of practice in coming budget years.