President Reagan, responding to the urgings of Chief Justice Warren E. Burger and White House counsel Fred F. Fielding, has removed former senator Roger W. Jepsen (R-Iowa) as the prospective chairman of a commission designed to honor the 200th anniversary of the Constitution, officials said yesterday.

Jepsen instead has been given what one official called "a consolation prize" of a six-year term as director of the National Credit Union Administration. The post pays $73,600 a year.

A senior official said that Burger, supported by Fielding, prodded the administration to "upgrade" the commission by moving aside Jepsen, who was defeated for reelection last year after a sharply negative campaign in which his character was a major issue.

"The chief justice wanted this commission to amount to something and become institutionally important, particularly at a time when it seems possible that we might have a new constitutional convention," said one official, who predicted that Burger will be selected chairman.

He was referring to a pending call for a constitutional convention to consider an amendment making it harder for Congress to pass an unbalanced budget. It has won approval of the 32 state legislatures, two fewer than needed for a convention to occur.

The commemorative commission would have no legal authority over such a convention, but it could be influential in national debate if such a convention were called.

Technically, Jepsen was never named chairman of the Commission of the Bicentennial of the U.S. Constitution, which was established by Congress in 1983. The law requires that the commission choose its chairman.

But administration officials said in January that the chairman would be Jepsen, who was defeated after a campaign in which he acknowledged that "in a moment of weakness" he had visited a Des Moines health club that had "nude encounters."

The choice stirred several protests, officials said, including a private one from Burger, who by law will belong to the 23-member group.

"This commission is important to Warren Burger because the Constitution is important to him," said one official.

Another official said it was also important to Burger because he wants to be chairman and has a good chance of being selected.

Burger is one of three members, along with the speaker of the House and the president pro tem of the Senate, who hold membership on the commission by virtue of their office. The chief justice, speaker and president pro tem each appoint four members; the other eight members are appointed by the president.

Reagan delayed appointments until after the election last November.

"We wanted to see who was available," an official said. "Frankly, there were an awfully lot of people who wanted to be appointed."

Officials said yesterday that all eight of Reagan's appointees have been chosen but have not been announced pending routine security clearances. They said the administration does not have a candidate in mind for the chairmanship.

After his defeat Jepsen was placed on the Justice Department payroll at an annual salary of $70,500 a year and detailed to the White House.