The hard server from Thornhill, Ont., fired 25 aces in the win, but had 34 unforced errors and converted three of nine break point opportunities.
Raonic, the No. 7 seed at the All England Club, is coming off a quarter-final appearance of the Aegon Championships in London last week. That was his first tournament since returning from a foot injury that caused him to miss the French Open.
Raonic made it to the semifinals at Wimbledon last year before losing to Switzerland's Roger Federer in straight sets.
Eugenie Bouchard of Westmount, Que., and Vancouver's Vasek Pospisil will play their first-round matches Tuesday.