President Carter charged yesterday that American business has "grossly distorted" the administration's labor law revision bill but predicted its passage after a "long and bitter battle" in the Senate.

Carter thus plunged into the lobbying war between business and labor over the measure, which is backed by both the White House and organized labor, but which conservatives have pledged to fight with a filibuster when it comes before the Senate next week.

Carter renewed his support for the proposal at a White House breakfast that also produced a pledge by the Senate Democratic leadership to keep the bill under consideration until the threatened filibuster is broken.

The bill, which would set deadlines to thwart delays in union representation elections and stiffen penalties for employers who violate organizing and collective bargaining laws, passed the House last year. Its backers claim enough votes for passage in the Senate, but concede it may take a number of cloture votes to get the 60 votes necessary to end debate. That has prompted speculation that the Senate leadership might be forced to withdraw the bill to avoid a second long seige in the wake of protracted debate over the Panama Canal treaties.

However, Sen. Alan Cranston (D-Calif.), Senate majority whip, told the 100 labor and congressional supporters of the bill at the breakfast that the measure will not be withdrawn before it can come to a vote on its merits. "We'll keep at it until we get cloture," he said.

Labor lobbyists said yesterday they previously had received such assurances in private but not a public commitment.

Carter's criticism of the business community for its tactics in lobbying against the labor bill followed presidential rebuffs to the legal and medical professions during a tour of Western states last week.

He did not dwell extensively on arguments by business lobbyists that the bill would lead to compulsory unionism, small business bankruptcies and higher inflation but said the business campaign generally amounted to a "grossly distorted" picture of what the bill would do.

HE calltd it a "moderate" measure that simply "lets the laws on the books be enforced for a change" and eliminates use of delaying tactics as a "weapon" in labor-management disputes.

Among other things, the bill would set deadlines of 30 to 75 days for holding union representation elections, provide time-and-one-half back pay for workers dismissed illegally for union activities, permit the government to bar repeated violators from getting federal contracts, require employers to compensate workers for wage and benefit improvements lost during illegal bargaining delays and give unions more job-site access to workers during organizing drives.

Carter's criticism drew an immediate retort from the U.S. Chamber of Commerce, a leading business opponent of the bill. "It is very distressing the the president choose to attack organizations instead of discussing the merits of the issue," said Chamber President Richard L. Lesher.

Labor Secretary Ray Marshall and AFL-CIO President George Meany came down harder on the business lobby than Carter during the breakfast, which had been billed as a combination strategy session and "pep rally" by its labor and administration organizers.

Marshall described the campaign against the bill as "expensive, distorted and shrill," while Meany accused the bill foes, including "the blue chip corporations of America . . . the most 'responsibile' corporate leaders in this country," of supporting a campaign of "deliberate lies" about the legislation.