WARSAW, Poland (AP) _ Peace activist Tom Hayden and his wife, actress Jane Fonda, on Wednesday urged the U.S. government to press for improved human rights in Poland.

''Our chief impression is that the lifting of (U.S.) sanctions has not been accompanied by any guarantees of the protection of human rights for individuals or groups like Solidarity,'' said Hayden.

''The U.S. government has a responsibility to swiftly indicate that our interest in human rights remains firm ... before (Polish) authorities take it as a sign that the West is going to fall asleep.''

Hayden, who said he also spoke on his wife's behalf, was interviewed by The Associated Press before the couple left for Vienna, Austria, and their Los Angeles home.

During their four-day visit, Hayden and Miss Fonda traveled to Gdansk to meet Lech Walesa, a founder of the outlawed Solidarity labor movement. They also met former Solidarity underground leader Zbigniew Bujak and senior Solidarity adviser Adam Michnik. Bujak and Michnik were freed from prison under a government amnesty last year.

Miss Fonda and Hayden also saw Polish government spokesman Jerzy Urban, Minister of Culture Aleksander Krawczuk, and the deputy speaker of the Polish parliament, Mieczyslaw Rakowski.

Hayden, a former radical activist who is now a Democratic member of the California Legislature, said opposition leaders he met supported President Reagan's decision last week to lift remaining U.S. sanctions against Poland.

The sanctions had banned official government credits and denied most favored nation trading status to Poland. They were among steps taken to protest the 1981 martial law crackdown on Solidarity, the first free trade union in the Soviet bloc.