Sixteen former high-ranking federal officials yesterday announced formation a group to monitor what it described as "regressive actions" by the Reagan administration and Congress on civil rights.

The group, which includes four former Cabinet members--two of them Republicans--and six former members of the U.S. Civil Rights Commission, charged that the administration and Congress have moved systematically to weaken or eliminate government methods of protecting against discrimination based on race, sex, age or handicap.

Arthur S. Flemming, the former Republican secretary of health, education and welfare, whom Reagan dismissed as chairman of the Civil Rights Commission last year, said the group's first priority will be to study Senate-passed legislation that would bar federal courts from ordering busing to achieve desegregation. The administration has endorsed the legislation, which the Senate approved as an amendment to the Justice Department authorization act.

Flemming was careful not to criticize new members of the Civil Rights Commission, whom the Senate is expected to confirm on Wednesday. He said he hoped that his new group, called the Citizens Commision on Civil Rights, would complement the watchdog activities of the government agency. Many activists are concerned about the integrity and independence of the commission with its new membership.

Flemming said his main concern was the increased use of riders to legislation, which he said, have threatened a host of civil rights, and often passed without prior warning and with little debate.

"It is an effort to substitute for the Supreme Court the Congress of the United States and that to me is very serious," he said. "People who want to oppose civil rights laws have become that desperate and they are willing to go that far to eliminate civil rights."

Among other matters for the group's attention, Flemming listed the curtailment of desegregation aid to schools; new restrictions on the Legal Services Corp.; the narrowing of affirmative action regulations; and the administration's position on tax exemptions for private schools that discriminate.

The group also includes two other former secretaries of health, education and welfare -- Wilbur Cohen and Elliot L. Richardson--and former labor secretary Ray Marshall.