Pioli's deparature comes with the Chiefs on the verge of hiring Andy Reid as their new coach, according to league sources.
"After several productive conversations, we made the difficult decision to part ways with Scott Pioli and allow him to pursue other opportunities," Chiefs Chairman and CEO Clark Hunt said. "Scott has been an invaluable member of the Chiefs family since joining us in 2009, and we sincerely appreciate his tremendous contributions over the last four years.
"I know that this was a difficult decision for Scott as well. He has a great deal of appreciation for the history of this franchise, for our players, coaches and employees, and especially our great fans."
Pioli, 47, joined the Chiefs in 2009 after nine seasons with the Patriots, where he helped to build New England's dynasty. But he failed to turn around the Chiefs, who were 23-39 in his four seasons, including a woeful 2-14 in 2012 under Rome Crennel, who was hired to replace Todd Haley during the 2011 season. Crennel was fired after this season