Per club policy, financial terms were not disclosed. According to TSN of Canada, Marchand's deal is worth $5 million.
The 23-year-old finished his first full NHL season with 21 goals and 41 points in 77 regular-season games.
He was a primary factor in the club's first Stanley Cup win since 1972, tallying 11 goals -- including two in the Bruins' 4-0 title-clinching Game 7 victory in Vancouver -- and 19 points over 25 playoff tilts.
In 97 games over the last two years with Boston, the Nova Scotia native has compiled 42 points and 71 penalty minutes.