The Buddhist monk offered his views on the hot-button social issue during his latest tour of the United States, where he was welcomed Thursday in Washington by top lawmakers and offered the customary prayer that opens each Senate session.
The Dalai Lama, in an interview, said that gay marriage was up to each government and was ultimately "individual business."
"If two people -- a couple -- really feel that way is more practical, more sort of satisfaction, both sides fully agree, then okay," he told an online talk show by veteran radio and television host Larry King.
The Dalai Lama said though that people should still follow their own religions' rules on sexuality.
"But then for a non-believer, that is up to them. So there are different forms of sex -- so long (as it is) safe, okay, and (if both people) fully agree, okay," the Dalai Lama said in English.
"Bully, abuse -- that's totally wrong. That's a violation of human rights," he said.
The Dalai Lama is Tibet's exiled spiritual leader and one of the most prominent leaders in Buddhism.
Gay marriage has won growing acceptance in the Western world and Latin America. But no predominantly Buddhist nation allows gay marriage, although several places with Buddhist influence including Nepal, Taiwan and Vietnam have increasingly debated the issue.
The Dalai Lama, who fled his Chinese-ruled homeland for India in 1959 and later won the Nobel Peace Prize, has prided himself on progressive positions and described himself as a feminist.
But his past comments on gay rights have occasionally bothered some of his Western audiences. In one of his books, the Dalai Lama, while not explicitly criticizing homosexuality, said that sex should only involve "organs intended for sexual intercourse."
- 'The leading nation' -
The Dalai Lama, whose meeting on February 21 with President Barack Obama was angrily condemned by China, separately told lawmakers that one of his main goals was "preservation of Tibetan culture."
Offering advice as a "longtime friend" of the United States, the Dalai Lama said that he considered the nation to be "really a champion of democracy, freedom."
"These traditional values are, I think, very, very relevant in today's world. After all, you are the leading nation in the free world, So, (show) self-confidence," the Dalai Lama said.
The Dalai Lama sat between House Speaker John Boehner, who said he wanted to show bipartisan support for the Buddhist monk, and the Republican leader's often bitter rival Nancy Pelosi, a longtime activist on the Tibetan cause. He later met top senators.
"What is happening in Tibet is a challenge to the conscience of the world," said Pelosi, the leader of Obama's Democratic Party in the House of Representatives.
More than 120 Tibetans have set themselves on fire in recent years to protest what they describe as a stifling Chinese control over their religious, cultural and political freedoms. Obama called for the protection of Tibetans' rights in a statement after his meeting with the Dalai Lama.
- Reflecting on mortality -
In contrast to his meeting with Obama, which the White House took pains to portray as private, the Dalai Lama was accompanied in his talks at Congress by Lobsang Sangay, who was elected in 2011 as the prime minister of Tibetans in exile.
The Dalai Lama told the lawmakers that he had transferred his political role to the elected leader.
While the globe-trotting monk has been instrumental in throwing a worldwide spotlight on Tibet, he has increasingly been looking ahead to the future of the movement without him.
The Dalai Lama appeared to reflect on his own mortality as he served as the guest Senate chaplain.
Offering prayers to the Buddha "and all other gods," the Dalai Lama recited what he described as "my favorite prayer," which he recites daily for inner strength.
"As long as space remains, as long as sentient beings remain, until then may I too remain to help dispel the misery of the world," he said.