He follows Welsh duo Richie Rees and John Yapp, as well as Georgian No 8 Dimitri Basilaia, into the Scottish capital club's squad for next season. Head coach Michael Bradley has also signed Northampton Saints full back Greig Tonks and Cheetahs prop Willem (WP) Nel.
"Ben has proven his ability on some of the toughest stages in world rugby and will be a formidable option at centre and full-back for Edinburgh Rugby for at least the next two seasons," said Bradley.
"He's a very impressive package of agility, power and skill, accommodating 100 kilograms of muscle into a 5'10" frame, and I believe he'll make a big impact at this club, both from a performance perspective and in bringing on the many talented young players we have at the club.
"This season Edinburgh made history by reaching the Heineken Cup semi-final for the first time, but we're not finished yet. We want to be challenging for honours in all competitions and believe we are making the right appointments in the right places to mount that kind of campaign in the seasons ahead."
Atiga will join from the Super 15 side the Highlanders having previously played for Auckland Blues from 2004-2008. While in Auckland he helped them win the Air New Zealand Cup three times.
As well as test honours at 15-1-side, Atiga helping the All Blacks win the IRB World Sevens Series at Twickenham in 2007. He took a year out from the sport in 2009 before joining Otago and earning selection for the Highlanders.
"It all happened very fast, probably in the space of about three weeks. The club were very interested in what I could bring to the table from a playing perspective but Michael also explained that he would be looking for me to play a leadership role and help bring on young Scottish players, a role which I've played with New Zealanders for the last couple of seasons and one which I'm looking forward to doing for Edinburgh," said Atiga.
"I toured Scotland with my school in 2000, with New Zealand Schools in 2001 and was based in Edinburgh with the New Zealand U20 side in 2004, when the Junior World Championships were in Glasgow, so it's reassuring to have experienced my new home through rugby already.
"Playing rugby overseas has always been something that's appealed to me. I've had loads of calls from fellow players at home and abroad telling me how beautiful the city is and how lucky I am to get this opportunity.
"I'm delighted to have signed and now just looking forward to getting on the pitch for my new club and doing my best for Edinburgh Rugby."
Born: 5 May, 1983 in Auckland, New Zealand
Ht / Wt : 1.80m ( 5'10") /100kg (15st 10lb)
International Honours: New Zealand U19, U20, 7s, All Blacks (1 cap, v Tonga (rep) 2003)
Provincial Debut: Auckland v North Harbour (2002)
Super Rugby Debut: Blues v Chiefs (2003)
Super Rugby Caps: 46
Super Rugby Points: 75 (6 tries, 6 conversions, 11 penalties)