A group of handicapped Americans plans to stage a sit-in protest next week at the offices of the Department of Health, Education and Welfare in 10 cities if HEW Secretary Joseph Califano does not approve immediately a series of civil rights regulations to benefit the disabled.

Dr. Frank Bowe, director of the American Coalition of Citizens with Disabilities, which represents a large segment of the nation's 28 million handicapped, said veterans wounded in Vietnam, other disabled adults and handicapped children and their parents will take to the street to "tell their stories." They may number in the thousands, organizers said.

"Disabled people throughout America have waited many years for laws and regulations which would help to bring us into the mainstream of society," said Bowe, who is dear. "The law was passed three years ago and the regulations to implement the law have been sitting on Mr. Califano's desk since the day he took office. He has refused to sign them."

At issue is Section 504 of the Rehabilitation Act of 1973, which prohibits discrimination against disabled citizens by recipients of U.S. funds. The law guarantees the handicapped equal rights in 16,000 school districts, 8,000 colleges and universities and numerous hospitals and other institutions.

Although detailed regulations to implement Section 504 had been presented to former HEW Secretary David Mathew, he left office without signing them.

When Califano became HEW Secretary, members of the disabled community expected him to sign the regulations immediately.Instead, Califano ordered a task force to study them and prepare a report for him on the issues involved.

"The Secretary did not want to sign regulations and put his name on a document when he was not sure of what the consequences of the new regulations would be," said Peter Libossi, HEW general counsel-designate.

"The feelings of the disabled community are not unjustified," said Libossi. "These people have suffered injustices for a long time. They finally get a bill past Congress. And now the Secretary won't sign."

Bowe said Califano had been notified that he has until April 4 - next Monday - to sign the regulations, or that protests would begin the next day at HEW headquarters here and at regional offices in Boston, Seattle, New York, Atlanta, Philadelphia, Chicago, Dallas, San Francisco and Denver.

"With each day that the 504 regulations go unsigned, there is an increased chance that certain provisions will be watered down," said Bowe. Already, he said, there is a proposal to change a provision in the regulations to provide education for handicapped children.

Libossi said the proposal is among several suggested changes in the regulations. He said no major changes in the regulations would be made by Califano until members of the disabled community are given an opportunity to comment.

According to Bowe, the protests will take the form of peaceful sit-ins and sidewalk demonstrations.