The club announced the move Tuesday, cutting ties with the 28-year-old who played six seasons with Cleveland Browns, Arizona Cardinals and Detroit Lions.
The Lions were high on McDonald early in training camp and he made a team-high seven tackles in B.C.'s 14-11 pre-season victory over the Edmonton Eskimos on Friday.
The University of Memphis product sat out last season after playing 80 games in the NFL, where he registered 216 tackles and nine interceptions.
The Lions play their second and final pre-season game Friday at B.C. Place Stadium against the Calgary Stampeders.
B.C. opens the regular season at home June 28 against Edmonton.