The vote is not binding on individual churches, but could cause some churches to leave the fold.
Roughly 80 percent of the members of the church's General Synod voted to approve the resolution. They debated for about an hour before voting.
On Sunday, a committee of about 50 United Church of Christ representatives gave nearly unanimous approval to the resolution, recommending that the General Synod approve it. It was supported by the UCC's president, John H. Thomas.
Traditionally strong in New England, the liberal denomination of 1.3 million members has long been supportive of gays and lesbians.