"I am committed and determined to deliver winning football to the city of Jacksonville," Jaguars owner Shad Khan said in a statement.
"Realizing that goal requires a fresh start throughout our football operations, and with that in mind I spoke this morning with Doug Marrone to express my gratitude for his hard work over the past four seasons as the head coach of the Jacksonville Jaguars."
Marrone joined the Jaguars in 2015 as an assistant head coach and offensive line coach. He took over as interim coach the next season after the franchise fired former coach Gus Bradley.
Marrone posted a 23-43 record in Jacksonville. He went 15-17 in two seasons as coach of the Buffalo Bills in 2013 and 2014 before he joined the Jaguars staff.
The Jaguars went 10-6 and reached the AFC Championship game in Marrone's first full season. The franchise then posted a 5-11 record in 2018 before a 6-10 campaign in 2019.
The Jaguars won their first game this season before 15 consecutive losses. Jacksonville's defense allowed the second-most points and yards in the NFL in 2020. The Jaguars offense scored the third-fewest points in the league.
"I'll always appreciate Doug's passion, grit and class, and I'm confident he will enjoy success in the next chapter of his career," Khan said.
"As the search for our new general manager continues, now the quest begins to find a head coach who shares my ambition for the Jacksonville Jaguars and our fans, whose loyalty and faith are overdue to be rewarded."