O'Malley recently wrapped up his 16th season as the head coach of the Sacred Heart women's ice hockey program in 2018-19.
Before taking over at Sacred Heart, O'Malley was the head coach at Wayne State for four seasons and a coach at Boston College for fifteen seasons. In taking over at Wayne State in 1999, he was saddled with the task of building a varsity program from the ground up for the second time in his career. He was an integral part of building the Boston College women's program in the 80's and was the coach when BC made the jump to Division I for the 1994-95 season.
O'Malley, a Boston native, graduated from Boston College with a bachelor's degree in economics from the College of Arts and Sciences in 1989. He played college hockey at BC under coaches Len Ceglarski and Steve Cedorchuk.
- On November 14, 2014, he won his 100th career game in charge of the Pioneers as SHU opened up play in its new arena, The Sports Center of Connecticut, with a 4-0 victory over SUNY Canton.
- In 2005-06, O'Malley guided the Pioneers to the ECAC Open Tournament Championship, defeating Saint Anselm for the crown.
- Led SHU to the finals of the ECAC championship for three consecutive seasons, between 2004 and 2006.