Kahui will head to Japan to play for the Toshiba club for two seasons at the end of this year's Super rugby season.
"I love being a Chief, but it is no secret that I have had my fair share injuries which have forced me to make some very hard decisions about my future and make the most of the opportunities while I can," Kahui said this evening.
Chiefs' coach Dave Rennie said Kahui had played more than 50 games for the team and had been an outstanding member of the Chiefs family.
"I have been really impressed with him as a man, as a player and as a leader within our group. He has an opportunity to set himself up for his future and we are fully supportive of what he is doing and hope to get him back for 2015, Rennie said.
Kahui has played 17 tests for the All Blacks since making his debut in 2008 and has scored 10 tries.
The 27-year-old, who missed the international season last year after shoulder reconstruction - his fourth - is an outstanding test player at either centre or wing and the All Blacks view him as a critical part of their armoury.
The two-year Toshiba deal will enable him to return to New Zealand to play Super rugby in 2015 and possibly push for a World Cup place.
The Chiefs head to Mangatainoka for a warm-up game against the Hurricanes on Saturday ahead of the first round of the Super rugby against the Highlanders in Dunedin February 22.
