He said:" It's obvious to everybody at the Ospreys that there are great things happening here, we've got a quality squad and great coaches, there's a real buzz about the place and we're confident about our chances for the new season. It's clearly something that any player would want to be a part of.
"Last season was a fantastic one for me. I really made my mark in the side, had plenty of game time, made the Wales squad and now I want to build on that over the next four years.
"There are plenty of good centres at the Ospreys so I can't take anything for granted, but the situation is that the competition for places will benefit me, will benefit the Ospreys, and will benefit Wales.
Ospreys coach Sean Holley added: " Andrew has already proven his worth to the Ospreys with more than 70 appearances to his credit already, and last season we really saw him starting to make an impact. He got his reward for an excellent year when he was called up for the South Africa tour and I'm sure that the experience will be of immense benefit for him this year as he looks to push on to the next level.
"The centre position is one where we have strength in depth and I'm looking forward to seeing Andrew providing real competition for the likes of Gavin Henson and Sonny Parker over the coming season and beyond."
Bishop made his Ospreys debut against Borders in February 2005 and has established himself as a key member of the squad since then, clocking up 76 appearances for the region, with 20 of those coming during the 2007/08 campaign. He has five tries to his credit, the most memorable of which came at Twickenham in April when he crossed the line against Leicester Tigers to set the Ospreys on their way to EDF Energy Cup glory.
His consistency was recognised by Wales coach Warren Gatland when he was named in the national squad for the trip to South Africa in June, and he made his full international debut coming off the bench during the second test.
Wales internationals Gavin Henson, Jonathan Thomas, Shane Williams, Lee Byrne, Paul James and Huw Bennett, former All- Black Filo Tiatia and youngsters Ben Lewis, Ed Shervington, Leigh Bevan, Gareth Owen and Rhys Webb have all signed new long-term deals with the Ospreys during 2008.