Virginia Sen. John W. Warner, who has made several recent overtures to the state's black community, earlier this month delivered a commencement address to a segregationist private academy that has been the center of a national controversy over racially discriminatory private schools.

The speech has kicked off a storm of criticism from state civil rights organizations, particulary in light of Warner's vote last week for extension of the Voting Rights Act. The Virginia state chapter of the American Civil Liberties Union charged yesterday that the Republican senator was "lending support to racist attitudes" by speaking to the graduating class of the Prince Edward Academy in Farmville, Va., an all-white school academy that was founded during the days of the state's "massive resistance" to school integregation.

"Blacks view this as an insult," added James Ghee, a Farmville lawyer and vice president of the state conference of the NAACP. "We believed he Warner was above and beyond having anything to do with this type of school. If it had been the other senator -- Harry F. Byrd Jr. -- that would have been understandable."

The attacks clearly hit a senitive nerve with Warner, who has emphasized his accessibility to black leaders in recent months and who last week broke with Byrd by voting for the Voting Rights measure. Upon learning of the criticism yesterday, Warner telephoned Jack Gravely, executive director of the Virginia NAACP, and invited a reporter to his Senate office to discuss the speech.

"Should I deny people the opportunity to meet and hear from their senator just because of the actions of the school hierarchy?" Warner said. "I represent every single citizen of this state equally."

Warner also said that it took courage for him to accept the school's invitation. "I could have made a safe political choice" and refused , he said. "That would have been the easy thing to do. But I had the courage to consider it my duty to speak so that I could establish a bridge between the principles to which I adhere and this remaining pocket of sentiment in Virginia."

The senator, however, later said that, although he had accepted the invitation a year ago, he didn't "focus" on the school's discrminatory background until he was being driven to Farmville for the June 4 speech. He also said that he did not use the occasion to talk about racial issues and instead gave what a staff member described as "your standard inspirational" commencement address.

Prince Edward County catapulted into attention in 1959 when officials shut down the public schools in the rural Southside community rather than bow to court orders to integrate. The academy was founded the same year with considerable local support as a symbol of Southern defiance.

In 1978, the academy became the first private school to have its tax-exempt status revoked under Internal Revenue Service guidelines requiring that private schools publicly state they are nondiscriminatory in hiring and admissions. Earlier this year, when the Reagan administration announced that it was no longer enforcing the guidelines, Prince Edward was featured as a prime example of the kind of institution that would benefit from the policy.

Warner emphasized yesterday that he was opposed to granting tax exemptions to segregated schools such as Prince Edward. He also urged that his decision to speak at the academy be examined in light of his overall record, particularly his recent support for the Voting Rights Act.

NAACP director Gravely said that while he was pleased with Warner's support of the act, he noted that the senator also voted for 14 unsuccessful amendments that would have weakened the law. After speaking to Warner, Gravely said he also believed that the senator was embarrassed by his address to Prince Edward.