The moves Friday came a day before NFL teams must reduce their rosters to the regular-season limit of 53.
The Patriots also released offensive linemen Jonathan Compas, Mike Berry and Corey Woods, tight end Carson Butler, wide receiver Buddy Farnham, running back Richard Medlin and defensive lineman Darryl Richard.
Brown spent the past five seasons with the Oakland Raiders as a backup linebacker and special teams player. In 55 games, he made 13 starts. The Patriots signed him on Aug. 20.
Richard, a seventh-round draft choice in 2009, was on injured reserve all last season. Berry, Medlin and Woods were rookie free agents.