The 22-year-old Bath flyer sustained the injury during a session at the team’s training camp in Brighton on Tuesday.
However, he did not suffer the broken jaw in the same session and has returned back to his club, Bath.
It was the final session before head coach Eddie Jones names his final squad for the four tests against South Africa, Fiji, Argentina and Australia.
Bath director of rugby Todd Blackadder said: "Anthony Watson broke his jaw in the England training camp earlier this week.
"It's too early for a full medical prognosis on how long he'll be out for, but it's likely he'll miss the autumn internationals.
"He's in great hands with our medical team, and we look forward to seeing him back on the pitch when he's ready."
The winger will be a big loss to England having scored 12 tries in 24 appearances and starring in the Red Rose’s 3-0 whitewash away to Australia during the summer.
Watson’s Bath teammate Semesa Rokoduguni is the most likely replacement having earned his solitary international cap two years ago.
With Watson and Jones joining James Haskell on the sidelines, the England management are desperately hoping for some good news from Owen Farrell’s back problem, while captain Dylan Hartley is also struggling with a similar injury.Reuse content