The House Committee on Foreign Affairs passed the bill despite intense lobbying by Turkish officials and opposition from President George W Bush.
The vote was a triumph for well-organised Armenian-American interest groups that have lobbied Congress for decades.
Defence Secretary Robert Gates reiterated his opposition to the resolution, saying the measure could hurt relations at a time when US forces in Iraq rely heavily on Turkish permission to use their airspace for US air cargo flights.
Relations are already strained by accusations that the US is unwilling to help Turkey fight Kurdish rebels based in northern Iraq.
About 70% of US air cargo headed for Iraq goes through Turkey, as does about a third of the fuel used by the US military in Iraq. US bases also get water and other supplies by land from Turkish truckers who cross into the northern region of Iraqi Kurdistan.
Historians estimate up to 1.5 million Armenians were killed by Ottoman Turks around the time of World War I, an event widely viewed by scholars as the first genocide of the 20th century.
Turkey, however, denies the deaths constituted genocide, saying the toll has been inflated and those killed were victims of civil war and unrest.
“It is not possible to accept such an accusation of a crime which was never committed by the Turkish nation,” the Turkish government said yesterday.
“It is blatantly obvious the House Committee on Foreign Affairs does not have a task or function to rewrite history by distorting a matter which specifically concerns the common history of Turks and Armenians.”
Armenian President Robert Kocharian has welcomed the vote, saying: “We hope this process will lead to a full recognition by the United States of America... of the genocide.”
Speaking to reporters yesterday after meeting European Union foreign policy chief Javier Solana, Mr Kocharian also appealed to Turkey to join talks on restoring bilateral relations.
Turkey is under no pressure from the EU to call the Armenian killings genocide.
The European Commission criticised France last year for making it a crime to deny the killings were genocide, calling the bill counterproductive during a critical stage in Turkey’s EU entry talks.