Ventura, 46, has led the White Sox since October 2011, and the team has gone 148-176 the last two years. Chicago was 63-99 in 2013; only the Houston Astros lost more games in the American League.
Terms of Ventura's contract weren't released.
"We have been on the same page since Day One but I'm very happy to have this behind us so we can continue to keep our focus on the playing field," Ventura said in a statement.
"I'm excited about the direction of the club and the moves we have made this offseason, but there is still a lot of work to be done so I think we're all ready to get to spring training and get started."
'How to Train Your Dragon 2' releases 5-minute clip
Moore to attend retreat in to avoid Kutcher's wedding