Sen. Robert P. Griffin (R-Mich.), 53, a veteran of 10 years in the house and nearly 12 in the Senate, announced yesterday that he will not seek re-election to the Senate when his term expires next year.

"Twenty-two years is long enough. I've decided not to run again," Griffin said in a statement.

"I would like to become better acquainted with my family; and all of us would like to spend a lot more time at our home in Traverse City," he said, adding that he would like to do "some writing, perhaps some teaching, and I may return to the practice of law."

Griffin's announcement caught Michigan representatives at the Republican National Committee meeting in Chicago by surprise. However, sources there close to the Griffin family said the senator's wife, tired of the strains of political life, "has been urging him to step down for some time."

An associate of Griffin speculated that Griffin's 19-to-18 defeat for the republican leader post in the Senate by Howard H. Baker Jr. (Tenn.) Jan. 4 may have been a factor. "I think the only thing he wanted was to be minority leader, and when he lost that, well . . . "

Griffin aides in Washington said his health is excellent, discounting that as a possible cause. Two potential Republican nominees for the post are Gov. Willaim. G. Miliken and ex-Rep. Marvin L. Esch, who lost to Don Riegle (D-Mich.) last year in a race for the Senate. Democratic possibilities include several members of the Michigan congressional delegation.

Griffin first gained fame in 1959 when, as a second-term congressmen, he cosponsored with Phil M. Landrum (D-Ga.) a tough House bill restricting the activities of labor unions, which was eventually passed and signed into law as the Landrum-Griffin bill. In 1965 he was one of a team of young congressmen who united behind Rep. Gerald R. Ford (R-Mich.) to oust Charles A. Halleck Ind.) from GOP leadership of the House and put Ford into the job.

When Ford moved up to the Presidency in 1974, Griffin remained a close confidant, and he was floor manager of Ford's successful bid for the Republican Presidential nomination at the 1976 Republican Convention.

After a decade in the House, Griffin moved to the Senate in 1966, first gaining appointment to a vacancy and then winning election over G. Mennen (Soapy) Williams, the popular former Democratic governor. He won re-election in 1972 using a powerful campaign against school busing as one of his main themes.

An extremely soft-spoken and cautious man in public, Griffin is an excellent behind-the-scenes operator and in 1969 won the GOP whip spot, a job held for seven years.

Griffin is the fourth senator up for re-election in 1978 to announce recently that he won't run again. Carl T. Curtis (R-Neb.), William L. Scott (R-Va.) and James Abourezk (D-S.D.) made similar announcements in recent months. Lee Metcalf (D-Mont.) indicated some time ago he would not seek re-election, and Sens. John J. Sparkman (D-Ala.) and John L. McClellan (D-Ark.) are considered good possibilities to retire because of their age.