The team announced her passing Thursday morning ... saying, "While we are sad, we are comforted knowing Virginia Halas McCaskey lived a long, full, faith-filled life and is now with the love of her life on earth."

"She guided the Bears for four decades and based every business decision on what was best for Bears players, coaches, staff and fans."

McCaskey was the longest-tenured owner in the NFL ... leading the team since her father and founder of the franchise -- George Halas -- passed away in 1983.

During her time as the principal owner, she helped oversee the only Super Bowl win in franchise history, which came in 1986 when they defeated the Patriots 46-10. The Bears also won five straight division titles from 1984 to 1988.

Around that same time, she famously disbanded the team's cheerleading squad ... claiming it was sexist and degrading to women.

She married Ed McCaskey in 1943 ... and they had 11 children together, with more than 21 grandchildren, 40 great-grandchildren and four great-great-grandchildren.