Lam to lead Bristol
The back row forward takes on the leadership duties from fellow Samoan international David Lemi.
The 28-year-old has made 30 appearances for the club in two seasons, scoring 17 tries.
A hugely popular figure among players and supporters, Lam won the Championship Player of The Year award in 2016.
"It's a great honour for me to lead this team and to captain Bristol," Lam said.
"Everybody is working so hard as a tight-knit unit and we're focused on the new season.
"This is a fantastic environment to be involved in and I will be giving my utmost – on and off the field – to help drive the club forward."
Lam, who joined Bristol from Hurricanes in 2014, underwent foot surgery during earlier this year.
"Jack assumes an important role within the squad – it's a position I was keen for him to take on," Director of Rugby Andy Robinson told bristolrugby.co.uk.
"Jack is a player that always leads by example on the field and lifts the performances of the players around him. He's diligent and professional in his preparation and a positive role model for the group.
"On behalf of everybody at the club, we thank David Lemi for his efforts as captain last season.
"David remains a key member of our squad and a senior figure that has shaped the culture and mindset of the club. He will continue to provide guidance to Jack as the new campaign gets underway."
