The growing national nuclear freeze campaign today scored its greatest political triumph to date when supporters submitted about 750,000 signatures to a California initiative petition, apparently ensuring a November vote on the freeze issue in the nation's most populous state.

Harold Willens, chairman of the California campaign, supervised the delivery of petitions with 188,000 signatures to the Los Angeles County registrar-recorder's office here, likening the petition drive to the 1978 California Proposition 13 campaign which "was the catalyst for what became a nationwide taxpayer revolt, so-called."

Campaign workers delivered petitions today to county offices all over the state in a drive that appears to have collected more than twice the required 346,119 signatures.

"We want this campaign to help change the whole international climate in which our elected representatives deal with the nuclear arms race," said Willens, a Los Angeles businessman.

According to the national campaign's office in St. Louis, nuclear freeze proposals could be on the ballots of eight states and the District of Columbia by November. California's will be by far the most politically potent, but it will not be the first. The Wisconsin legislature two weeks ago approved placing a resolution on the Sept. 14 primary election ballot calling for negotiation of a "moratorium and reduction" in world nuclear weapons production.

Petition campaigns to put various nuclear freeze resolutions on state ballots are proceeding in Michigan, Arizona, Oregon, Montana and D.C. Legislatures in New Jersey and Delaware also have proposals for November freeze votes.

The California initiative urges the U.S. government to propose to the Soviet Union a joint agreement "to immediately halt the testing, production and further deployment of all nuclear weapons, missiles and delivery systems in a way that can be checked and verified by all sides."

Even Republican conservatives in California have signed the initiative, calling it a fairly innocuous expression of concern about the arms race, but President Reagan and Secretary of State Alexander M. Haig Jr. have opposed the idea of a freeze.

Without the threat of a further increase in U.S. nuclear arms and delivery systems, they argue, it will be impossible to persuade the Soviets to negotiate what they say both the Reagan administration and freeze advocates want--a reduction in nuclear arms.

Willens and Jo Seidita, who started the initiative campaign in California with her husband, Nicholas, said today they will run full-page advertisements in 28 California newspapers Wednesday to begin the "education, outreach and fund-raising" phase of the campaign.

Willens, standing between the 13 cardboard boxes of signed petitions brought here by armored car, said the campaign spent about $375,000 to finance a largely volunteer effort collecting petition signatures and now hopes to raise about $1.5 million to promote a favorable vote in a state where a January poll already has shown 60 percent of voters in favor of the initiative.

Seidita said fund-raising concerts, dances and $10-a-plate dinners will be held in the coming week with more events due. Willens said the California campaign curtailed national fund-raising after a complaint from an out-of-state freeze advocate.

Willens called the Reagan administration's insistence on maintaining a threat of a new arms race to force the Soviets to bargain "Alice in Wonderland logic" which voters would reject in November.

He emphasized that the proposed freeze must include the Soviets and be verified by both sides. "We don't trust the Soviets more than anyone else," he said.