On March 2012, Jennings was re-signed to a 2-year contract, and was later reunited with former Colts teammate Kelvin Hayden. Against his former team in the season opener, Jennings intercepted first-overall draft pick Andrew Luck twice, marking the first time in Jennings' career that he recorded two interceptions in a single game. He also forced another interception by deflecting Luck's pass to safety Chris Conte. The following week, Jennings recorded five tackles, two passes defended, and intercepted Aaron Rodgers in a 23–10 loss to the Packers. After week three of the 2012 season against the St. Louis Rams, Jennings became the first Bears player to record an interception in four consecutive games (dating back to the 2011 season finale) since Dave Duerson in 1986. Jennings was later named the NFC Defensive Player of the Month for September. His seven interceptions led the NFL. In Week 13 against the Seattle Seahawks, Jennings sustained a shoulder injury, and was ruled out of the following game against the Minnesota Vikings. Jennings was replaced by former Colts teammate Kelvin Hayden. As of Week 16, Jennings led the Bears with 15 pass breakups, and his three games with more than one interception is a team record. On December 26, Jennings was named to his first career Pro Bowl. Jennings finished the season with nine interceptions, leading the league, making him the first Bears player since Mark Carrier in to lead the league in interceptions. Jennings was later named to the second team of the 2012 All-Pro Team, his first.