A spokesperson for Police Scotland said: “At around 7.20pm on Sunday, 8 July, police received a report of a 17-year old man in the water in Loch Lomond, north of Luss.
“Emergency services attended, and the man was taken to the Royal Alexandra Hospital where he later died. A post mortem examination will take place in due course, however, there are no suspicious circumstances surrounding the death.”
The special operations team from the Scottish Ambulance Service also attended and took the young man to the hospital in Paisley.
A spokesman for the Loch Lomond Rescue Boat, which also attended the incident, said it was possible that the teenager may have got out of his depth as part of the loch quickly becomes deep.
Situated in southern Scotland it has a maximum depth of 153 metres and covers an area of 44 square miles.
The rescue boat service has been issuing advice for staying safe around the loch during the warmer weather.
The spokesman said one part of the loch that was particularly important to be aware of was like “a shelf”.
“It goes out quite shallow and drops off quite quickly into deep water,” he said. “That’s what catches a lot of people out.”
The teenager is the second person to die in the lake in recent days after the body of a 25-year-old man was recovered from the water last week.