A bill that stigmatizes gay people and forbids participating in gay pride activities was passed in Russia by a unanimous 436-0 parliamentary vote.
One member of parliament out of 437 abstained at least.
Before its passage, more than two dozen protesters were attacked by hundreds of anti-gay activists and then detained by police in the nation's capital.
The new bill will fine individuals organizing gay pride events up to 5,000 rubles ($156) and fine companies (including media) up to a million ($31,000).
Foreign citizens involved can be deported or jailed.
The bill banning the "propaganda of nontraditional sexual relations" still needs to be passed by the appointed upper house and signed by President Vladimir Putin.
Neither step is in doubt, however.
The measure is part of an effort to promote traditional Russian values instead of Western liberalism, which the Kremlin and the Russian Orthodox Church are opposed to.
They see this as corrupting Russian youth and contributing to the protests against Putin's rule, and hostility to homosexuality is shared by much of Russia's political and religious elite.
Lawmakers have accused gays of decreasing Russia's already low birth rate and said they should be barred from government jobs, undergo forced medical treatment or be exiled.
The State Duma passed another bill on Tuesday that makes offending religious feelings in Russia a crime punishable by up to three years in prison.
The legislation, which passed 308-2, was introduced last year after three members of the Pussy Riot punk group were convicted of "hooliganism motivated by religious hatred."
Both bills drew condemnation from Amnesty International.
"They represent a sorry attempt by the government to bolster its popularity by pandering to the most reactionary elements of Russian society," said the group.
John Dalhuisen, the human rights group's Europe and Central Asia program director, lamented the decline "of fundamental rights and the expression of individual identities."
Needless to say, gay marriage is not legal in Russia.