California Gov. Edmund G. Brown Jr. came here last night to star at a fund-raiser for Democratic gubernatorial candidate Theodore G. Venetoulis, a man Brown described as a "good friend, a good man, and I hope the next governor of Maryland."

As he returned to the state where he scored his first victory over Jimmy Carter in the 1976 presidential primaries Brown told the crowd of 250 people, "I have neither a suitcase nor a carpet bag, but only a lot of good wishes for Ted Venetoulis."

When the California governor arrived here for a four-hour stopover on his way home from the national Governors Conference, Brown was asked if this visit signaled his entry into the 1980 presidential race.

"No," Brown replied, "I just stopped in because I was in the neighborhood." Venetoulis later said "actually everybody thinks Gov. Brown came to see me but Linda Ronstadt is still in town."

Last spring, when Venetoulis, the Baltimore County Executive, was out in California attending a conference he had asked Brown to help him in his campaign this summer. But only last Thursday, as Brown was preparing his itinerary for the governors' conference, did Venetoulis receive Brown's assent to spend a few hours helping Venetoulis raise money.

With only two weeks left until the Sept. 12 primary, the Venetoulis camp is short $50,000 needed for a planned advertising campaign. They quickly threw together this fund-raiser in suburban Baltimore, inviting 300 guests of whom 250 came.

It was Venetoulis who in 1976 masterminded Brown's upset victory over President Carter in the Maryland presidential primary.

Brown's first victory in a presidential primary was hardly the work of one man. Walter S. Orlinsky, Baltimore City Council president and another contender for the Democratic gubernatorial nomination, also helped Brown's primary effort by polling the state.

Now, Orlinsky is furious with what he calls Brown's carpetbagging. "One year ago, Brown promised me he would not be involved in Maryland politics," Orlinsky said yesterday. "He said he had enough problems in California. This just shows me he's a liar, what else can I think of him."

Orlinsky also has wondered aloud whether it is such a coup to have Brown campaigning for Venetoulis since "Brown is the guy who brought Proposition 13 on America because he couldn't get along with his state legislature and built up a $5 million surplus."

Brown made it clear last night that he remembered making no promise to Orlinsky and that he thought Venetoulis was "a little better than the other fellows running for governor." Brown said he thought Orlinsky had a "pretty active imagination." Then he started to talk about Proposition 13 - the measure approved by California voters early this summer that mandates severe cutbacks in the state's property tax assessments.

"As you know I opposed Proposition 13 but luckily there is forgiveness. I'm a born-again tax-cutter. "I'm going to cut the income tax and California is going to have an $8 billion tax cut," Brown said.

When Brown was asked if his visit to Maryland would alienate the state's old guard politicians who had also helped him in his presidential primary here he answered, "Ted is a break with the past and an opening to the future . . . but sometimes the past should evolve into the future."

When asked about suspended Gov. Marvin Mandel, who also supported Brown, the California governor replied, "There should always be forgiveness of sins."