Douglas H. Ginsburg, the assistant attorney general who heads the U.S. Justice Department's antitrust division, is the leading candidate for the U.S. Court of Appeals seat vacated in June by J. Skelly Wright, Reagan administration sources said yesterday.

A background check on Ginsburg, 40, is under way, and official announcement of his nomination could come soon, sources said.

Ginsburg, who has headed the antitrust division for a year, is one of the administration's leading proponents of industry deregulation and is its point man for a far-reaching package of proposed antitrust amendments that centers on a more lenient stand on merger enforcement.

He previously was the Office of Management and Budget's administrator for information and regulatory affairs, and he served as deputy assistant attorney general for regulatory affairs in 1983 and 1984.

Georgetown University's Robert Pitofsky said Ginsburg's nomination would be a "continuation of the program by Attorney General Edwin Meese and President Reagan to fill the courts of appeals with very conservative judges who have developed their ideological positions and who will not vary much from them."

"These judges will keep carrying out the Reagan ideology for another decade," said Pitofsky.

The appointment also would follow the administration's general practice of naming to appeals courts academics who have little trial or court experience.

Pitofsky described Ginsburg as a "very able and thoughtful person" who "does not take himself too seriously."

Ginsburg could not be reached for comment.

If confirmed, Ginsburg would be the seventh person named by Reagan to the 12-judge court. In addition, Antonin Scalia, whom Reagan named to the appeals court here, has been nominated by the president to the Supreme Court. Confirmation hearings on Scalia's nomination are set for Aug. 4 and 5.

Although administration officials have begun compiling names of possible appointees, sources said that Scalia's seat is not considered vacant and that it will be several weeks before a possible successor is named.

Wright, 75, who has served on the appeals court since 1962 after more than a decade as a U.S. district judge in Louisiana, took senior status on June 1 because of his health and age. He has been a key liberal on the court, which has a conservative majority for the first time in decades.

Before joining the administration, Ginsburg was a Harvard Law School professor from 1981 to 1983 and an assistant professor from 1975 to 1981, specializing in antitrust and economic regulation.

A graduate of Cornell University and the University of Chicago Law School, Ginsburg served as a clerk for the U.S. Court of Appeals and for Supreme Court Justice Thurgood Marshall.