A man has been seriously injured after falling from a tram following a dispute in Melbourne's CBD.

The 59-year-old man fell from the tram’s top step onto the road as he and another man were leaving the tram at the Domain Interchange just before 11pm on Thursday, police said.

It is believed he'd had an altercation with the second man just beforehand.

The victim was taken to the Royal Melbourne Hospital with serious, but non-life-threatening injuries.

Police are seeking a man described as in his late teens, of Pacific Islander appearance, with short, dark hair, and wearing navy-coloured shorts and a spray jacket.He was last seen walking near the Shrine of Remembrance.

AAP