Team physician Pat Connor, who repaired Newton's partially torn rotator cuff in March 2017, performed what the team described as arthroscopic surgery.
In an Instagram post Thursday night, Newton called it a minor setback and thanked fans for their support.
Newton missed the final two games of the 2018 season because of soreness in his throwing shoulder, which prevented him from attempting deep passes and ultimately made other passes difficult.
The soreness first became an issue following an Oct. 21 win at Philadelphia in which the 2015 NFL MVP had to throw 22 times in the fourth quarter to overcome a 17-0 deficit.
The soreness got worse as the season progressed, contributing to a seven-game losing streak after a 6-2 start.
"As Cam's shoulder got worse, that made it much harder to win,'' team owner David Tepper recently said.
At the time Tepper spoke, the team was formulating a plan for how to handle Newton's shoulder. Tepper said then that "all options'' were being considered.
"Hopefully, Cam's shoulder is fantastic, right? And we're hunky-dory, all fantastic,'' Tepper said. "If it's not, you may need more cap space. You may need to go out and find [another quarterback]. If you don't, you guys are going to be writing what a dope we are here. Why did we make these other moves?
"So think about that. You want to keep your options open, put yourself in best position as you can to win, and I'm talking again for the long term.''
Newton's rehabilitation from the surgery will begin immediately. In 2017, he didn't throw during offseason workouts or at a June minicamp. He was limited throwing for much of the preseason and during the week once the season began.
Coach Ron Rivera and offensive coordinator Norv Turner agreed after this past season there was a "sense of urgency'' about Newton's shoulder.
Although Newton completed a career-best 67.9 percent of his passes -- he came into the season with a career average of 58.5 -- the Panthers had to bring backup Taylor Heinicke in on multiple occasions to throw a Hail Mary at the end of a half or game.
The offense prospered in the season finale, a 33-14 victory at New Orleans, with third string quarterback Kyle Allen bringing the deep pass back to the game plan.
Newton admitted after his final start that dealing with the shoulder pain had become frustrating.
"I wish I could say what the injury is, because I really don't know what it is, either," Newton said after a completing a season-worst 55.2 percent of his passes in a 12-9 loss to New Orleans. "No matter how much you push, no matter how much you ice, [how many] anti-inflammatories you take ... trust me, I did it. Acupuncture, massages, it's not been a time a night went by I didn't have some type of work done on my arm.
"We just don't have the strength."