Rosie O’Donnell‘s ditching her sweet mansion on Miami’s Star Island — and based on these pics … we can’t understand why she’d ever leave.

As we told you last week, Rosie just put the pad on the market — asking price $19.5 million — and it includes waterfront views and a massive aquarium in the dining room.

If you’re one of the Mega Millions winners — feast your eyes on these shots around the 11,000 sq. foot spread … it could all be yours!