The unanimous vote sent the bill back to the Senate, which voted last year to also bar timber from Myanmar, also known as Burma.
House Foreign Affairs Committee Chairman Howard Berman said the legislation would put financial pressure on a corrupt regime that failed to adequately help its citizens recover from a cyclone and famously put down democracy demonstrations by Buddhist monks last year.
"The legislation before the House today hits the regime where it hurts - in the wallet," Berman, a Democrat, told the House. "By blocking the import of Burmese gems into the United States and expanding financial sanctions, the legislation will take hundreds of millions of dollars out of the pockets of the regime each year."
He said the 11,000-store Jewelers of America supports a ban on Burmese gem imports. Retailers like Tiffany's and Bulgari have also voluntarily made the ban their policy, Berman said.
The bill also gives Chevron incentives to divest its natural gas program in Myanmar.
It aims to bring more pressure against the junta to restore democratic civilian government in Myanmar. U.S. officials say Myanmar has been evading earlier gem-targeting sanctions by laundering the stones in other countries before they are shipped to the United States.
President Bush is eager to sign the bill, which will extend and harden sanctions Congress first passed in 2003. President Bush's wife, Laura, has emerged in recent months as a strong proponent of democratization in the Southeast Asian country.
Myanmar has been under military rule since 1962. The current junta took power in 1988 after crushing pro-democracy demonstrations at a cost of an estimated 3,000 lives. Its soldiers similarly cracked down on Buddhist monks during the so-called Saffron Revolution in September. Human rights observers put the death toll among demonstrators in the hundreds.