Evans, who began his career at Otago as a full-back, made his test debut for New Zealand against England in 2004 and won a total of 16 caps, scoring 103 points. He last played for the All Blacks at the 2007 Rugby World Cup.
The 36-year-old joined English Premiership side Harlequins in 2008 and went on to make 206 appearances for the club, scoring a club record 2,217 points with 30 tries, 309 conversions, 476 penalties and seven drop goals.
"I thought leaving New Zealand was hard, but leaving the game I've played since I was eight years old, and professionally for 17 years, is tough," Evans said.
"I need to thank the clubs I have represented, the coaches -- who have helped shape the player I am today -- and the fans, both in New Zealand where it all started, and here in the UK, for their support.
"I couldn't think of a better shirt and place to finish my career at than Harlequins."
Evans scored 20 points against Leicester Tigers in the 2011-12 Premiership final to secure Harlequins' first league title. He also kicked a touchline conversion to win the Challenge Cup in 2011.