Ronald Hainsey (born March 24, 1981, in Bolton, Connecticut) is a professional ice hockey defenseman who currently plays for the Atlanta Thrashers of the National Hockey League.

He was drafted 1st round, 13th overall by the Montreal Canadiens in the 2000 NHL Entry Draft, from collegiate team the University of Massachusetts Lowell. He has played with AHL teams, Quebec Citadelles and the Hamilton Bulldogs.

After spending 3 seasons in the Canadiens organization was claimed off of waivers on November 29, 2005, by the Columbus Blue Jackets, where he established himself into a leading two-way defenseman.