Desrosiers has confirmed the news on his own Twitter account -- "Excited to be a new member of Friartown! Go Friars," he wrote in a tweet.
The 6-foot-11 Windham, N.H. resident led Central Catholic to MIAA Division 1 state championships in 2008 and 2010, before moving on to Wake Forest. In two seasons in Winston-Salem, he averaged 4.4 points and 3.7 rebounds, with 38 starts, and totaled 112 blocks. His 52 blocks in 2010-11 were the most by a Wake freshman since Tim Duncan.
Desrosiers declared his intent to transfer late last March, and was released from his scholarship.
Per transfer rules, Desrosiers must sit out the 2012-13 season. He will have two years of eligibility remaining starting in the fall of 2013.
Desrosiers is the latest high-profile local to sign on with Friars head coach Ed Cooley. Providence also has commitments from South Kent swingman and Providence native Ricardo Ledo, the nation's No. 21 overall senior; and point guard Kris Dunn, a McDonald's All-American this past season out of New London (Conn.) High.