The investigation, which will be conducted by the Duma's information policy, technologies and communications committee, will check whether CNN, the Voice of America, Radio Liberty and "other American media" are complying with Russian law.
The statement said the Duma backed the move on Friday evening after Konstantin Zatulin, an MP from the pro-Kremlin United Russia party, proposed an investigation to retaliate for what he called a "repressive" U.S. move against Russian state-funded broadcaster RT.
He said he was referring to an initiative by U.S. Senator Jeanne Shaheen, who has introduced a bill to empower the Justice Department to investigate possible violations of the Foreign Agents Registration Act by RT.
Shaheen, a Democrat, cited a U.S. intelligence agency assessment that suggested RT was part of a Russian influence campaign to help Donald Trump win the White House last year. The Kremlin and RT have strongly rejected that allegation.