There will be little or no increase in world oil production in the next 20 years, a study released today by Congress' Office of Technology Assessment predicted.

The study, whose conclusions are somewhat more pessimistic than those of many other energy experts, examined the prospects for world oil production on a country-by-country basis, including current oil production capacity and the likelihood of new discoveries, as well as the political, ecnonomic and other factors that will affect production levels.

The OTA study, recognizing the large uncertainties involved in such forecasts, concluded that oil production in the non-communist world is likely to range between 45 million and 60 million barrels a day in 1985 and between 40 million and 60 million in the year 2000, compared to 52 million daily in 1979.

A recent forecast by Exxon Corp. projected non-communist oil output -- including liquids from natural gas -- at about 60 million barrels a day in 1990. Analyses by others, including Shell Oil Co., are somewhat more optimistic, primarily on the assumption that more oil will be recovered from existing fields than was assumed by Exxon.

U.S. production will drop from its current level of about 10.2 million barrels a day to between 4 million and 7 million daily by the beginning of the next century, the study said. The high end of that range assumes the annual addition of 1 million barrels of oil reserves and extensive use of enhanced recovery techniques.

Meanwhile, the communist world may cease to be a net exporter of oil within a few years, putting added pressure on world oil markets, the study added. In addition, consumption in non-oil-exporting developing nations will rise if they can find the means to pay for it.

The study acknowledged that it would be physically possible to increase oit output by up to one-third more than the upper edge of its range of estimates, but said such increases are unlikely because the nations that have the necessary reserves -- Saudi Arabia, Kuwait, the United Arab Emirates and Mexico -- have few financial or political incentives to raise their production levels so sharply.

Dr. John H. Gibbons, director of OTA, said, "If OTA's projections prove correct, the United States as well as the rest of the world will have to fuel its future industrial and economic growth without the seemingly limitless supply of oil we have had in the past. It is this prospect that lies at the heart of the challenge to science and technology in the 1980s."