Kim suffered a series of injuries and has not played a tour event since undergoing surgery on his left Achilles tendon, but has been working for months on a return to competition and had spoken with PGA Tour and LIV Golf officials.
"He oozes incredible talent," tweeted former world number one and LIV commissioner Greg Norman.
"The world has seen it in the past and now it is an honour... to give the opportunity for this star to be reborn.
"Welcome back and to the LIV Golf family mate. The golf world has missed you."
American Kim finished third at the 2010 Masters and made a record 11 birdies in his second round at Augusta in 2009.
On the PGA Tour, he won the National and Wachovia Championship in 2008 and the 2010 Houston Open and was ranked as high as sixth in the world in 2008.
Kim also played on triumphant United States teams at the 2008 Ryder Cup and 2009 Presidents Cup.
