Gov. Michael S. Dukakis (D-Mass.) disputed as "inaccurate" yesterday President Reagan's characterization of an innovative Massachusetts welfare program as a copy of something Reagan initiated when he was governor of California in the 1970s.

At his news conference Tuesday night Reagan said, "what Gov. Dukakis is doing in his state is what we did in California as part of our welfare reforms way back when I was governor there. And, when I got here, I had our people start informing the states of this." Reagan made the statement in response to a question about why his budget proposed to eliminate the federal program that provides most of the funds for the Massachusetts Education and Training Program, among other state work-incentive programs.

In fact, the California program to which Reagan referred was what is called a "workfare" program, which required that welfare recipients perform 20 hours a week of work in the community in exchange for their checks.

"That's inaccurate," Dukakis said of Reagan's assertion that California was the model for the Massachusetts program. "It reflects a lack of awareness of what's happening in a state like this one . . . . He's confusing what was a workfare program in California with what we're doing."

Reagan said of the California program that 76,000 people were "funneled through that program and into private enterprise jobs . . . . " This is a number he has repeatedly cited to reporters since he announced in his State of the Union address that the White House Domestic Council will produce a comprehensive study of the welfare system by Dec. 1 of this year. Reagan said in his news conference Tuesday, as he has said before, that his California program would be a good model for the country.

Evaluations of the Reagan workfare program, however, describe ineffectiveness and inefficiency. In 1974, the California auditor general issued a report saying that it had resulted in only 9,600 people being placed in jobs -- not 76,000.

"I don't know," said John Svahn, assistant to the president for policy development, about the accuracy of the president's remarks. Svahn was a welfare official in California when Reagan was governor between 1967 and 1974. "I'm not familiar with the auditor general's report. There was controversy at the end of Reagan's term about how effective the program was."

"On the whole it was a good program, but in terms of placing people, creating jobs, there was not much of that," said Frank Levy, a University of Maryland professor, who conducted a study of Reagan's record on welfare for the Urban Institute in 1978.

Reagan's workfare program, in fact, was terminated in 1975. More recently, California adopted a welfare program, supported by both Democrats and Republicans in the state, that is loosely modeled on the Massachusetts experiment: the Education and Training program, or ET.

The ET program, begun in 1983, gives welfare recipients, most of whom are single women with children, child care and transportation as they are trained for private sector jobs. Its federal funds come not from the Social Security Administration but from the Labor Department. According to Massachusetts officials, 23,000 participants have found jobs since the program began. The Reagan budget has targeted the entire program, the Work Incentive Program, for elimination.

Said Svahn about Reagan's description of ET, "What the president meant is that it is a workfare program. While I'm not intimately familiar with it, it is based on a workfare concept."

It is this contention that Massachusetts officials dispute. "Our program is the antithesis of Reagan's program," said Thomas Glynn, the state's deputy commissioner of public welfare. "His program was 100 percent make-work jobs. Our people have been placed in the private sector. He didn't have training. We have training. We have 6,000 businesses involved. He had none."

"Workfare has been a failure," Dukakis said in an interview. During his first term, he attempted to implement his own workfare program, but he junked it after reelection in 1982 in favor of the ET approach. "The new budget would effectively prohibit us from doing what we're doing . . . . The question is how you help people lift themselves out of poverty, when they are overwhelmingly single mothers with small children. Working off your welfare check in some public service job 20 hours a week is just not going to do it."