Palmer went 30-of-42 through the air, including a 91-yard scoring strike to Michael Floyd in the third quarter -- the longest of the veteran quarterback's career.
Floyd finished with six catches for 193 yards as the Cardinals (6-4) notched a third straight win
Larry Fitzgerald made six grabs for 61 yards with a score for Arizona.
Jacksonville (1-9), which corralled its first win of the season last week, couldn't follow up with another victory as Chad Henne was intercepted twice. He finished with 255 yards and a touchdown.
Ace Sanders led the Jaguars' receiving corps with eight catches for 61 yards.
Danny Noble netted a 62-yard touchdown grab on his first career catch for Jacksonville.