"Being coached by Ivan will really offer a new dimension to my game," Raonic said in a statement Friday. "He brings such a vast knowledge of the game and his recent experience on tour is a major plus for my development."
Ljubicic retired in 2012 with a career-high ATP World Tour ranking of No. 3. He turned pro in 1998 and captured 10 titles over 14 years, including an ATP Masters 1000 title at Indiana Wells in 2010, defeating Novak Djokovic, Rafael Nadal and Andy Roddick en route.
Raonic, from Thornhill, Ont., said he and Ljubicic had similar aggressive styles of play, "so he can definitely understand the mentality I have on court and areas where I can improve."
Ljubicic won a bronze medal in men's doubles at the 2004 Summer Olympic Games in Athens with Mario Ancic. He was also part of the Davis Cup champion Croatian team in 2005, holding the record of 11 "live rubbers" won in that season.
"Working with Milos will be a great challenge," Ljubicic said. "He already has great weapons and I am looking forward to helping him develop his game even further this season. Since I retired I have never been too far from the tour and I think that my familiarity with the tour can be of help to Milos."
Ljubicic and Raonic will be training out of the Monte Carlo Country Club in Monte Carlo, Monaco.