The 20-year-old has completed a medical with the Seagulls and agreed a two-year contract subject to international clearance.
Manager Chris Hughton said: “Vahid is a centre-forward with a good goalscoring record this year in Finland – we hope that is something he can replicate here in England.
“He’s a tall, powerful player, and he is someone we see as adding to our attacking options – but he’s a young player, and someone we would see as an option within the squad at this stage.
“I want to see him pushing for a place in the squad at some stage this season, but it’s likely he will begin by playing some games for our under-21s side to help him make the transition to English football.”
Hambo, who spent two years at Sampdoria’s academy, is currently sidelined by a minor ankle injury which is expected to rule him out for two to three weeks.