The Massachusetts State Police issued Pouncey the subpoena as he exited the team's locker room at Gillette Stadium.
According to Sports Illustrated, the subpoena is related to an investigation into former Patriots tight end Aaron Hernandez, who is a close friend and college roommate of Pouncey from their days together as teammates at the University of Florida.
The magazine claims sources indicated that the subpoena has to do with an investigation centering on Hernandez's potential involvement in interstate gun trafficking, not the pending murder trial.
Hernandez, 23, was indicted in August in the killing of 27-year-old Odin Lloyd, a semi-professional football player who was dating the sister of Hernandez's girlfriend. He pleaded not guilty to first-degree murder and five weapons-related charges last month and is being held without bail at a county jail.
Pouncey, who is in his third season as a starter with the Dolphins, remains friends with Hernandez, and during offseason he and his twin brother Maurkice were photographed in a South beach night club wearing "Free Hernandez" hats during their birthday celebration.
Dolphins officials denied comment when asked about the subpoena.