The D.C. Board of Education, which touched off an enormous, bitter controversy last time it evaluated a superintendent, has unanimously rated School Superintendent Vincent E. Reed's performance of the job during his first 16 months as favorable in a letter that rings with praise.

Earlier this month the board voted unanimously to adopt a letter commending Reed for his performance as superintendent and outlining future goals after a board member recommended setting up a regular evaluation process. The board also voted to have a board committee begin work on a review and evaluation process that will make ratings standard.

Reed and his staff have "performed in an exemplary manner during the first sixteen months," said the board in its letter. "The atmosphere of mutual respect and trust evidenced between the members of the Board of Education and yourself . . . and the relationship between you and your staff has been welcomed by the Washington, D.C. community," according to the letter.

The last time the board evaluated a superintendent, the superintendent was Barbara Sizemore, whose contract with the board called for such a review. The unfavorable evaluation of Sizemore, who the board found a poor administrator, touched off several months of mutual hostility and suspicion.

Reed replaced Sizemore as acting superintendent after she was fired in November, 1975. He was then appointed for three years in March, 1976.

"In several instances your accomplishments have exceeded the enumerated expectations of the members of the Board of Education," the board said in the letter, calling Reed's performance outstanding.

Specifically the board commended Reed for reducing the number of errors in the school system payroll. Errors, which used to be frequent, are now "the rare exception rather than the rule," the board said. The board said Reed had also made progress on other personnel matters and on the regular reporting of financial statues.

In the letter praising Reed, the board also outlined goals for the remainder of his term as superintendent. Among those, the board called for developing an effective truancy prevention program, encouraging more cooperation from agencies which provide health services for D.C. public school students and beefing up the school system's public relations operation to provide more information on testing, curriculum, graduation and promotion requirements, and textbook offerings.

The board also pledged its support to Reed and his staff for the future.