Lazor was with Cincinnati in the same role for two seasons before being let go at the end of the 2018 campaign.
Matt Nagy's offense largely disappointed in 2019, leading to changes for the unit. Chicago fired offensive coordinator Mark Helfrich after it ranked 29th in both yards per game and points per game.
Lazor has logged plenty of experience as an NFL assistant, coaching the Philadelphia Eagles' quarterbacks in 2013 under Chip Kelly and then serving as the Miami Dolphins' offensive coordinator from 2014 to 2015.
Along with Nagy, the 47-year-old will be tasked with developing quarterback Mitchell Trubisky and helping him to continue his late 2019 production into 2020.