The story was first reported by Sports Business Journal and has since been confirmed by NFL Network's Albert Breer.
Gronkowski was able to play in Super Bowl XLVI, but was limited by the high left ankle sprain he suffered during the AFC Championship Game. The normally explosive Gronkowski, who set NFL single-season records for touchdowns (17) and receiving yards (1,327) by a tight end, finished with two receptions for 26 yards.
Gronkowski is expected to recover in 10 weeks, according to the Sports Business Journal, which would get him back on the field in time for organized team activities in the spring.
The surgery was expected, as The Boston Globe previously reported the second-year player would likely need surgery to clean up the ankle after the season.