MALIBU, Calif. (AP) _ ''Tonight Show'' host Johnny Carson has married his girlfriend Alexis Maas, the entertainer's publicist announced Monday.

It was the fourth marriage for Carson.

Carson, 61, and Miss Maas, described by publicist Jim Mahoney as in her mid-30s, were married by Superior Court Judge William Hogoboom on June 20 at Carson's Malibu Beach home.

''The only other person in attendance was his brother Dick, a television director, who stood up for him,'' said Mahoney.

Carson and Miss Maas later left for the Wimbledon tennis matches in England, Mahoney said.

Miss Maas, a native of Pittsburgh, worked in a stock brokerage when the couple met at least four years ago in Malibu, said Mahoney. They were secretly engaged in December, he said.

Carson divorced his previous wife, Joanna, in 1983. The bitter settlement proceedings over the 10-year marriage made gossip column headlines for two years.

His other wives were the former Jody Wolcott and Joanne Copeland.