In a bid to reverse a steep slide in enrollment, Bowie State College, a predominantly black school that traditionally trained teachers, will drastically change its program to emphasize computer and technology courses for working adults, its trustees announced yesterday.

"We were kind of getting to the end of the line with Bowie," said F. Perry Smith Jr., chairman of the board of trustees that governs Bowie and five other Maryland state colleges. "With enrollment going down so much, we have to make changes. It's a question of survival."

Despite construction of more than $40 million in new buildings, enrollment at Bowie dropped by one-third during the past decade, to 2,233 students last fall. Almost half of them attend part-time.

Despite efforts to promote integration, undergraduate enrollment remains overwhelmingly black. About two-thirds of the graduate students are white, many drawn from new subdivisions near the college's 237-acre campus about 20 miles northeast of Washington. Overall enrollment at the state-supported college is about 65 percent black.

Under the new plan, announced at a press conference in the college's Thurgood Marshall Library, officials said the number of part-time and white students is expected to rise while the number of black undergraduates is likely to continue to fall,, making about a 50-50 balance of the races.

Although some students and faculty members expressed uneasiness about the shift, Marcellina M. Brooks, acting president of the college, said, "We don't have a concern about who our students are. We are concerned that we have students.

"We know of our black heritage," Brooks continued. "And we are proud. But we are concerned with educating students--period."

Brooks took office last week after the sudden resignation of Rufus L. Barfield, Bowie's president since 1978. Barfield, who said he quit for personal reasons, could not be reached for further comment. But sources close to the board said he had lost the support of the trustees who were disappointed in the continued enrollment drop, including a 12 percent loss in the past year.

Under the new program, board chairman Smith said, the college would emphasize "bread and butter training that . . . relates directly to careers in high technology and health, the military, government, and industry."

Its centerpiece, he said, would be a new Academy for Computer Training that would offer "hands-on insturction in computer use."

A report, prepared by consultants from the Academy for Educational Development and endorsed by the board, calls for establishing a new bachelor of technology with 10 different specialities; bachelor's and master's degrees in computer science, and a master's in management information systems.

The college also plans to set up new master's programs in nursing and personnel training.

Other colleges in the Washington area and around the country also are making efforts to enroll more adults with programs oriented to technology. Any new programs at Bowie must be approved by the Maryland State Board for Higher Education.

Jean E. Spencer, executive director of state college trustees, expressed confidence that most of Bowie's new programs could start operating next fall or in 1984. She said the changes would be made without additional state funds, by shifting money and faculty away from unpopular programs.

New students will come "through aggressive recruitment and marketing," she said. "We have the facilities. We have the faculty, and there is the need. We are committed to putting them together."

Because of the enrollment decline, dorms that used to be crowded now have unfilled beds. Students say classes have been canceled because not enough people sign up for them. Under state funding formulas, which are tied to enrollment, relatively little money has been available to buy books for the new library, which now has large empty areas and many half-filled shelves.

Even so, costs have soared to $3,654 per student in state funds (in addition to tuition) this year. That is higher than any of Maryland's public colleges or universities except the Eastern Shore branch of the University of Maryland, which also is a small, predominantly black institution.

Spencer said Bowie State would use some its available space for a computer center that the trustees are moving from Towson State. She said community colleges would be invited to offer classes on the campus. But she said a proposal, made several years ago and repeated in the consultant's report, to start a branch of the University of Baltimore law school probably would not be carried out.

"We honestly believe that we're not just filling space now that we've built it," Spencer said. "We think there's a vast educational need by part-time adult students and for training in the new technology. We're going to reach out and serve it."