Key leaders of the AFL-CIO have privately worked out a tentative agreement to readmit the Teamsters union, 30 years after the union was expelled from the labor federation for corruption, labor sources said yesterday.

The move is expected to generate controversy within the 12.6 million-member AFL-CIO, but appears to have strong support among top leaders who negotiated the agreement with Teamsters President Jackie Presser in the past week. The Teamsters executive board voted earlier this week to return to the labor federation, sources said.

"The AFL-CIO has just received an application for affiliation from the Teamsters. AFL-CIO President Lane Kirkland said the application will go before the executive council" Saturday, a federation spokesman said late yesterday.

Sources close to the negotiations said the reaffiliation vote could be prevented only by a sudden groundswell of opposition at next week's AFL-CIO convention in Miami Beach. But sources indicated that was unlikely.

In the past, the Teamsters have shown little interest in joining the AFL-CIO, at least in part because of the union's success in gaining thousands of new members by raiding AFL-CIO unions. Sources speculated yesterday that Presser and the Teamsters are more willing to join the federation because of the union's latest legal problems with the federal government.

The Justice Department, in an unprecedented move, is threatening to take over the Teamsters in a civil suit that asserts the union is controlled by organized crime interests. Presser, meanwhile, as the fourth Teamsters president to be indicted, is facing trial in Cleveland on fraud and racketeering charges. Presser's salary has fluctuated, but he has earned more than $700,000 in a one-year period as Teamster chief.

While some unionists are expected to oppose the Teamster move because of the union's history of corruption, most union leaders will support it, a key AFL-CIO official said: "We ought to try to have a good image, but give me a choice between the role of public opinion and the role of increased power, and I'll take power."

The addition of the 1.8 million-member Teamsters would give the AFL-CIO substantial new legislative and political clout as well as new weapons in labor's efforts to unionize the burgeoning service sector of the economy, according to proponents of the reaffiliation move.

It would increase AFL-CIO membership by nearly 15 percent at a time when union membership has been falling dramatically. Dues-paying membership in the AFL-CIO today is just 80,000 more than it was when the federation was founded in 1955.

The Teamsters have one of the largest political action committees in the labor movement and are considered by many to be among the most effective lobbies on Capitol Hill. The union, the only major labor organization to endorse President Reagan in the 1980 and 1984 elections, maintains close ties to Republicans and Democrats.

Perhaps even more important to the other AFL-CIO affiliates, the Teamsters often are crucial to organizing and strikes in the construction and retail service industries because Teamsters members control the flow of material and goods.

The Teamsters, whose traditional strength was in the trucking industry, have diversified substantially in recent years, adding hundreds of thousands of members in professions ranging from accountants to zoo keepers. The union also has many public sector workers, including police officers and prison guards.

The importance of the Teamsters in the construction and service industries was underscored by the fact that the two people most instrumental in the effort to get the union back into the federation were Robert A. Georgine, president of the AFL-CIO Building and Construction Trades Department and William H. Wynn, president of the United Food and Commercial Workers Union. The UFCW represents workers in the supermarket and retail sales industries.

"It is quite appealing to unions in those industries, because now you would have the Teamsters with you, instead of possibly crossing picket lines to make deliveries," said a ranking AFL-CIO official who has supported the reaffiliation move.

"This also gives us the ability to launch massive organizing drives" in which the Teamsters could join with AFL-CIO unions to recruit new members, an AFL-CIO official said, adding, "The more major players you have, the greater potential for taking on big targets."

Sources close to the negotiations said the move to bring the Teamsters back into the federation was renewed last week when Wynn and Georgine met with Presser at Teamsters headquarters in Washington. They said the meeting was set up by Edward T. Hanley, the president of the Hotel Employees and Restaurant Employees International Union, who has long had close ties with the Teamsters.

At that meeting, sources said, Presser expressed desire to return to the AFL-CIO. Georgine and Wynn then met with Kirkland and Thomas R. Donahue, secretary-treasurer of the federation, who approved the return, subject to approval by the biennial convention.

On Tuesday, Wynn and Georgine met with the Teamsters board outside of Orlando, Fla., and the board voted for reaffiliation.

The late AFL-CIO president George Meany was adamantly opposed to allowing the return of the Teamsters, a union he expelled from the federation in 1957 as part of an effort to rid the trade union movement of corruption. Four of the last five Teamster presidents, dating back to the 1950s, have been indicted on corruption charges. Three were convicted and jailed.

For several years, Kirkland has taken a much different stance on reaffiliation. "Every sinner belongs in the church, and every union belongs in the house of labor," he has said.

The move for reaffiliation will be discussed Saturday in Miami Beach by the federation's 35-member Executive Council, some of whose members had not been informed of the move until yesterday. "A lot of people would like to smoke the peace pipe," said one labor expert with close ties to the AFL-CIO leadership. He said that if the vote were close in either the Executive Council or the convention "it wouldn't be a smart thing to oppose it" because it would be taking on the federation's top leadership.