Meredith was writhing in pain for a few minutes before being helped onto the cart with an air cast supporting his left leg. He had been tackled low by safety Johnathan Cyprien after a 16-yard reception. His left leg twisted upon contact as he braced for the hit.
The Bears quickly ruled Meredith out for the game.
Meredith -- a former undrafted free agent -- led the Bears with 66 receptions for 888 yards and four touchdowns last year.
He had missed a portion of the Bears' offseason program after tearing ligaments in his thumb, but the 6-foot-3 receiver returned for training camp and appeared to develop a strong chemistry with starting quarterback Mike Glennon.
Losing Meredith for any extended period of time would be devastating for the Bears, who allowed receiver Alshon Jeffery to leave via free agency in the offseason. Chicago is also without veteran receiver Markus Wheaton, who is recovering from left finger surgery.
Bears long-snapper Patrick Scales also left Sunday's game with a knee injury.
ESPN's Jeff Dickerson and The Associated Press contributed to this story.