The attraction, which features sets, props and memorabilia from the BBC series, closed in London in February to make way for its move to Cardiff Bay.
The new 3,000 sq m building is at Porth Teigr, next door to the BBC’s Roath Lock studios, where Doctor Who, Casualty and Pobol y Cwm are produced.
The exhibition is expected to attract up to 250,000 visitors a year.
The internal fitting of the building will take place over the coming weeks.
YESSSSSSSSS! I NEED TO GO! since i didn’t get to when it was in london. plus next door to the studios?! then i can see all the sights in it and torchwood. WOO!