Michał Zalewski (born 19 January 1981) is a computer security expert from Poland.
He has been a prolific vulnerability researcher and a frequent Bugtraq poster since mid-1990s, and has authored a number of programs for Unix-like operating systems. For his continued research on browser security, he was named one of the 15 most influential people in security and among the 100 most influential people in IT. Zalewski is an employee of Google Inc.