Tasmania is to become the first state in Australia to recognise same sex marriages from overseas.

An amendment to Tasmania's Relationship Act was passed unopposed in the state's Upper House, meaning marriages performed in countries where it's legal will now be recognised in Tasmania.

A Gay and Lesbian Rights Group spokesman, Rodney Croome, has welcomed the move saying it shows Tasmania is becoming more tolerant.

"II think that something we can all be proud of that Tasmania's non-discrimnatory laws are being extended to ensure that everyone who travels to or moves to Tasmania can expect the same kind of legal protection to people who already live here," Mr Croome said.