Packers had secured their first win since October 18 to return to the top of the division on Sunday and they went looking for the offensive initiative early on, but their first drive was halted when they were held up on the fourth down in midfield.
The hosts' defence returned the favour with a three-and-out when Randall Cobb took a fair catch and punt at his side's 16, but they saw a golden chance to take the lead against their arch-rivals slip away when Davante Adams dropped a sure touchdown pass from Aaron Rodgers.
The Bears continued to struggle in the first quarter, missing four tackles and giving away two first downs through penalties, and after Packers caught them with another three-and-out they deservedly took the lead.
A clever screen play saw Rodgers find Eddie Lacy from 25 yards, and though the running back's touchdown was reviewed for a possible early release call, the ruling on the field was upheld as Rodgers became the fastest quarterback to reach 250 touchdown passes in NFL history.
Green Bay were good value for their lead, outgaining Bears by seven first downs to one in the first quarter, but they lost some momentum in the second as Lacy fumbled for the fourth times in his last five games and Chicago took full advantage, recovering and levelling the scores as Jay Cutler hit Zach Miller from three yards.
The Packers edged back in front through a Mason Crosby field goal after Jeff Janis had hit a 64-yard kickoff return to swing the pendulum back in their favour, but in the final minute of the first half, the Bears took the lead for the first time.
Cutler found Marquess Wilson for what looked like a 20-yard touchdown, and although Wilson was found to have grounded at the one-yard line upon a review, Jeremy Langford rushed in to hand the Bears the lead 30 seconds before the break.
Green Bay got themselves into field goal range with seconds to go and Crosby converted a 50-yarder to cut Chicago's lead to a single point at half time.