More: 9 Awesomely uplifting same-sex pregnancy announcements
The video, which was shared by a user on Sina Weibo (the Chinese equivalent of Twitter) shows a man getting down on one knee and proposing to his boyfriend by presenting him with a large jewellery box.
"Today, I invite all the people we know and do not know to bear witness", he said, according to Pink News.
The shocked boyfriend cannot believe it and gasps as his lover presents him with a watch before placing it on his wrist — which appears to signify that the young man has said "yes".
More: Magician's proposal to his girlfriend is nothing short of magical (VIDEO)
The pair then embrace while most of the commuters on the train cheer for them — although there were reportedly shouts of "sin" and "disgusting" from a few fellow commuters, The Telegraph reports.
Witnessing any proposal is special, but this one may be even a little more so, because China legalised homosexuality only in 1997. And while same-sex marriage is yet to be legal, this public declaration of love — and the public reaction to it — suggests that perhaps the country is becoming more progressive.
More: Sam Smith's 'Lay Me Down' video embraces marriage equality
Watch the entire proposal in the video below:
Gay couple get engaged on Beijing subway