Prince George's County school superintendent Edward J. Feeney yesterday reaffirmed his commitment to pay raises negotiated with teachers and other unionized employes last year, despite severe cuts in the school budget recommended by County Executive Lawrence J. Hogan.

"The contract agreements were negotiated last year in good faith," Feeney said in a statement. "It is not fair to place the burden of inflation and the effect of TRIM on the backs of school employes," he added.

Feeney said that money for the negotiated cost-of-living raise is his top priority.

School spokesman Brian J. Porter said that if Hogan's recommendation to cut the schools' budget request from $337 million to $301 million were implemented, it would require eliminating 744 more positions than the 324 the superintendent had proposed.

"The specific budget cuts outlined by the county executive would actually result in the immediate loss of between 1,000 and 1,500 jobs," Porter said, based on the effect of seniority and other ripple effects of cuts in the school budget.

While conceding that their original $337 million request will not be fully funded, Porter said school officials have not yet identified specific areas for cuts.

"We know that the budget situation will force layoffs," Porter said. "But whatever shape the eventual budget takes, no one is endorsing the shape proffered by the county executive."

Porter said a report yesterday that budget cuts would cause mass layoffs, reduce the teachers' pay raise, eliminate most assistant principals in junior and senior high schools and remove librarians from elementary schools was not what the superintendent was recommending, but was what Hogan budget analysts told school officials would occur if the executive's budget were approved by the County Council.

Hogan, in his budget message, suggested that volunteers could replace some of the personnel, but Porter disagreed.

"The clear implication is that teachers should become librarians, guidance counselors and health aides, that they should bandage cuts, file books, clean floors and still find time to teach . . . with less pay," Porter said.

A study released by the Maryland Department of Education yesterday showed that Prince George's continues to have the fewest teachers and other professional staff per 1,000 students of any school system in Maryland.

Nevertheless, Robert Duncan, Hogan's budget director, said some school employes must be cut because the proposed tax rate is the maximum permitted under the TRIM charter amendment, which limits revenue from property taxes to the 1979 level.

"The dollars are where the dollars are," said Duncan. "There are really only two issues--the pay issue and the program issue. There certainly isn't any issue about levying higher taxes."