The Grizzlies released a statement Tuesday after Williamson's wife, Nicole, notified team officials that he had died overnight.
Williamson, nicknamed "Eggman" in basketball circles, had just begun his sixth season with the Grizzlies. He previously spent three seasons with the Charlotte Bobcats, leading their scouting of college and high school prospects while assisting with the team's international scouting efforts. Williamson also worked as a New York Knicks scout from 1997-2003.
Before beginning his NBA career, Williamson worked 21 years as a college assistant at St. John's, Seton Hall, Columbia, Louisville, Iona and Florida State.
The Grizzlies will announce funeral arrangements and plans to honour Williamson at a later date.