The legislation has been praised by LGBTQ organisations, but strongly opposed by the Orthodox Church
Greece has become the first Christian Orthodox-majority country to legalise same-sex marriage.
Same-sex couples will now also be legally allowed to adopt children after Thursday’s vote.
Greek Prime Minister Kyriakos Mitsotakis said the new law would “boldly abolish a serious inequality”.
But the legislation has divided the country, with fierce resistance being led by the powerful Greek Orthodox Church.
The bill needed a simple majority to pass through the 300-member parliament.
Mr Mitsotakis championed the bill but required the support of opposition parties to get it over the line, with dozens of MPs from his centre-right governing party opposed.
“People who have been invisible will finally be made visible around us, and with them, many children will finally find their rightful place,” the prime minister told parliament during a debate ahead of the vote.
“The reform makes the lives of several of our fellow citizens better, without taking away anything from the lives of the many.”
The vote has been hailed as historic by LGBTQ organisations in Greece.
Fifteen of the European Union’s 27 members have already legalised same-sex marriage. It is permitted in 35 countries worldwide.
Greece has until now lagged behind some of its European neighbours, largely because of opposition from the Church.
It is the first country in southeast Europe to have marriage equality.
Supporters of the Church held rallies at Syntagma Square in Athens on Thursday. Many displayed banners, held crosses, read prayers and sang passages from the Bible.
News Related-
Russian court extends detention of Wall Street Journal reporter Gershkovich until end of January
-
Russian court extends detention of Wall Street Journal reporter Evan Gershkovich, arrested on espionage charges
-
Israel's economy recovered from previous wars with Hamas, but this one might go longer, hit harder
-
Stock market today: Asian shares mixed ahead of US consumer confidence and price data
-
EXCLUSIVE: ‘Sister Wives' star Christine Brown says her kids' happy marriages inspired her leave Kody Brown
-
NBA fans roast Clippers for losing to Nuggets without Jokic, Murray, Gordon
-
Panthers-Senators brawl ends in 10-minute penalty for all players on ice
-
CNBC Daily Open: Is record Black Friday sales spike a false dawn?
-
Freed Israeli hostage describes deteriorating conditions while being held by Hamas
-
High stakes and glitz mark the vote in Paris for the 2030 World Expo host
-
Biden’s unworkable nursing rule will harm seniors
-
Jalen Hurts: We did what we needed to do when it mattered the most
-
LeBron James takes NBA all-time minutes lead in career-worst loss
-
Vikings' Kevin O'Connell to evaluate Josh Dobbs, path forward at QB