Black conservatives who agree with the Reagan administration that legal racial discrimination is history and who cast the NAACP and other black groups as anachronisms from the civil rights era are "worse than mercenaries . . . , dupes or fools" and are helping to perpetuate evil, Benjamin L. Hooks said tonight.

The executive director of the NAACP, who had long softened criticism of the administration in hopes of meeting with President Reagan, spoke in tones unusually harsh for the moderate NAACP.

Giving the kickoff address at the group's annual convention, Hooks seemed less angry with Reagan than with his black supporters, who are frequently cited by the administration as a new breed of black leaders. White House aides earlier this year said their strategy for dealing with blacks is to seek out new leaders.

Reagan has not spoken before a traditional black group or met with their leaders in about three years. Earlier this year, a small group headed by Robert Woodson went to the White House to discuss the economic revival of black neighborhoods.

In addition, black Reaganites, including Clarence M. Pendleton Jr., head of the Civil Rights Commission; economists Walter Williams and Thomas Sowell, and Clarence Thomas, chairman of the Equal Employment Opportunity Commission, have repeatedly questioned the civil rights leaders' criticism of Reagan. They argue that budget cuts are economic issues that should not be seen in a civil rights framework and contend that the government has done most of what it can to protect blacks through existing civil rights laws.

"Then there are the Pollyannas of the administration, some of whom are black and shall remain nameless by me, who have proclaimed that all is well," Hooks said. "They do not say that blacks shall overcome, but that blacks have overcome.

"These apologists point out that in each and every instance blacks are treated fairly and equitably; that every barrier has been eliminated . . . , " he continued. "Therefore, they assert, we no longer need affirmative-action goals and timetables or judicial remedies. They further suggest, by their illogical logic, that the civil rights acts . . . were not only written by white men but for white men. This is a lie in the face of history."

In his speech tonight Hooks also said Senate confirmation of William Bradford Reynolds, the current head of the Justice Department's Civil Rights Division, to the No. 3 job at the department would "signal the surrender by our elected officials to the forces of darkness -- a Justice Department bent on bombing the 14th Amendment, hijacking the civil rights acts . . . and holding hostage those who have been locked out of the sunlight of opportunity."