President Reagan has been urged by senior advisers to endorse a report by his special envoy on acid rain that calls for a five-year, $5 billion effort by government and industry to test cleaner coal-burning technology, White House officials said yesterday.

Such an endorsement would be a major policy shift by Reagan, who has previously maintained that more study is needed on acid rain. The endorsement would also mark the first time Reagan has accepted the premise that acid rain is a manmade phenomenon.

While Reagan has not made a final decision, officials said he is expected to endorse the report during the March 18 visit here of Canadian Prime Minister Brian Mulroney, who has pushed hard for action by the United States on acid rain.

The report was prepared jointly by special U.S. envoy Drew L. Lewis and former Ontario premier William G. Davis.

At a meeting of the White House domestic policy council this week, Reagan was told by State Department officials that an endorsement of the document would provide a valuable boost to Mulroney, a fellow conservative who has been facing economic and political difficulties.

The president was also told that additional spending this year would not be required because Congress has appropriated most of the first-year money called for in the document, albeit against Reagan's recommendations.

The report recommends a five-year, $5 billion program to be split between government and industry for a commercial project to test cleaner methods of burning coal in U.S. factories and power plants.

The recommended first-year installment for the federal government would be $500 million. Congress has voted $400 million for a clean-coal technology project, which the administration reluctantly accepted, and about $80 million is being spent on related U.S. programs, officials said.

The report received a cool reception at the White House when Lewis presented it to Reagan Jan. 9. "We can't keep studying this thing to death," Lewis said then.

The president has privately questioned whether acid rain is a man-made problem and said he agrees with some experts who attribute it, at least in part, to natural causes.

According to many scientists, however, sulfur dioxide emissions from U.S. factories and plants -- concentrated in the industrial Midwest -- undergo changes in the atmosphere and fall to Earth as acidic snow and rain, damaging lakes, streams and forests in the northeastern United States and Canada.

There is a long-running dispute over the full nature of the problem, the costs of cleanup and how those costs should be borne by various regions and sectors of U.S. society.