Ronchi joins a strong Mumbai Indians line-up, which includes Indian superstars Sachin Tendulkar and Harbhajan Singh, Lankan duo Sanath Jayasuriya and Lasith Malinga, and recently-retired South African all-rounder Shaun Pollock.
"I can't wait to get over there and start training with the likes of Tendulkar and Jayasuriya and try to gain as much as I can from the wealth of experience they possess," Ronchi said.
"It will be a tremendous learning experience for me, not just in how to play Twenty20 cricket, but in all aspects of my game because I will be surrounded by so many champions."
"And there may be an opportunity to open the batting with Sachin in front of his home crowd in Mumbai - that would be the stuff dreams are made of."
Ronchi joins fellow Western Australians Mike Hussey (Chennai) and Luke Pomersbach (Mohali) in the IPL, as well as Warriors coach Tom Moody, who will be in charge of the Mohali franchise.
Moody said it was great news for Western Australian cricket to have another young player joining the IPL.
"Both Luke Ronchi and Luke Pomersbach should be proud of the recognition they have received," Moody said.
"It is a credit to themselves and a credit to WA cricket that two young players will play alongside the legends of world cricket, where they will develop their cricket experience and come back as better equipped players."
The IPL is scheduled to begin on April 18, with the final on June 1 in Mumbai.