Attorney General William French Smith yesterday blamed "politically motivated criticisms and irresponsible journalism" for what he called public misconceptions about "our impressive record of civil rights enforcement."

"I can only conclude, regretfully," Smith said in a speech in New York, "that some of these critics desire to create hostility among minority Americans. The motivation can only be political."

Smith did not specify the critics, directing his attack at "various public figures, many of them heads of civil rights organizations." A spokesman here, where the text of his remarks was released, declined to elaborate.

Until now, the attorney general's public-opinion campaign has stressed the positive civil rights accomplishments of the Reagan administration and asserted that only busing and quotas divide the administration from its critics.

Yesterday's remarks, which came toward the end of a 20-minute address to the Conference Board, an association of corporate executives, struck some civil rights leaders as an accusation of bad faith.

Ralph Neas of the Leadership Conference on Civil Rights and Judy Goldsmith of the National Organization for Women, in separate interviews, called Smith's speech an "escalation of rhetoric" and reacted angrily to the suggestion of political opportunism.

"President Reagan has been welshing on the national commitment to equality and civil rights," Goldsmith said. "The responsibility for the anger and hostility that Mr. Smith is referring to lies at Reagan's doorstep. I think it's irresponsible of them to be apparently trying to chill the public dialogue on extremely important human rights."

Benjamin Hooks, executive director of the NAACP, took a softer line.

"The NAACP is not trying to create a dispute where none exists," he said. "I welcome him citing instances of what the Justice Department has done, and I hope he will listen to the instances we want to talk about."