During the 2011 NHL Entry Draft, Burns, along with a second-round draft pick in 2012, was traded to the San Jose Sharks in exchange for Devin Setoguchi, Charlie Coyle and a first-round pick in 2011.
With a year still left in his contract with the Wild, Burns signed a five-year contract extension on August 1, 2011, with the Sharks; the deal would pay him $28.8 million over five years, with an average salary cap figure of $5.76 million.
In 2013, after rookie defenceman Matt Irwin's acquisition by the Sharks, in March, Burns was moved to forward, where he scored 20 points in 23 regular season games.
In the 2013–14 season, Burns played the first eight games of the season, but missed 13 games after October 21 due to sore gums.
On November 21, Burns returned to the Sharks' line-up and scored a goal against the Tampa Bay Lightning in a 5–1 winning effort.
On November 29, against the St. Louis Blues, Burns recorded his first career hat-trick in a 6–3 victory.

In August 2014, the Sharks announced that Burns would move back to defense where he scored 17 goals and finished tied for second among NHL defensemen with 60 points.
Burns also won the NHL Foundation Player Award for outstanding charitable and community work.

He had a breakout season in 2015–16, finishing with 75 points (27 goals, 48 assists), then had 24 points (seven goals, 17 assists) in 24 Stanley Cup Playoff games to help the Sharks reach the Final for the first time since entering the NHL in 1991.

On November 22, 2016, Burns signed an eight-year $64 million contract extension with the Sharks through 2024–25, with an average annual value of $8 million per year.

In 2017, Burns won the James Norris Memorial Trophy as the league's best defenceman.
He was also nominated for the Ted Lindsay Award, awarded annually to the league's best player as voted by the National Hockey League Players Association.

He played in his 1000th career game on December 27, 2018, in a 4–2 win over the Anaheim Ducks.
During the 2011 NHL Entry Draft, Burns, along with a second-round draft pick in 2012, was traded to the San Jose Sharks in exchange for Devin Setoguchi, Charlie Coyle and a first-round pick in 2011. With a year still left in his contract with the Wild, Burns signed a five-year contract extension on August 1, 2011, with the Sharks; the deal would pay him $28.8 million over five years, with an average salary cap figure of $5.76 million. In 2013, after rookie defenceman Matt Irwin's acquisition by the Sharks, in March, Burns was moved to forward, where he scored 20 points in 23 regular season games. In the 2013–14 season, Burns played the first eight games of the season, but missed 13 games after October 21 due to sore gums. On November 21, Burns returned to the Sharks' line-up and scored a goal against the Tampa Bay Lightning in a 5–1 winning effort. On November 29, against the St. Louis Blues, Burns recorded his first career hat-trick in a 6–3 victory.
In August 2014, the Sharks announced that Burns would move back to defense where he scored 17 goals and finished tied for second among NHL defensemen with 60 points. Burns also won the NHL Foundation Player Award for outstanding charitable and community work.
He had a breakout season in 2015–16, finishing with 75 points (27 goals, 48 assists), then had 24 points (seven goals, 17 assists) in 24 Stanley Cup Playoff games to help the Sharks reach the Final for the first time since entering the NHL in 1991.
On November 22, 2016, Burns signed an eight-year $64 million contract extension with the Sharks through 2024–25, with an average annual value of $8 million per year.
In 2017, Burns won the James Norris Memorial Trophy as the league's best defenceman. He was also nominated for the Ted Lindsay Award, awarded annually to the league's best player as voted by the National Hockey League Players Association.
He played in his 1000th career game on December 27, 2018, in a 4–2 win over the Anaheim Ducks.
Brent Burns