The 32-year-old will now become a free agent when the market opens on July 1 after spending 12 years with the Heat. Power forward Udonis Haslem will also leave the club this summer.
"Today we were notified of Dwyane's intention to opt out of his contract and Udonis's intention to not opt into his contract, making both players free agents," the Heat president Pat Riley said in a statement.
"Dwyane has been the cornerstone of our organisation for over a decade, and we hope he remains a part of the Heat family for life.
"We look forward to meeting with Dwyane and Udonis and their agent in the coming days to discuss our future together."
The Heat lost the NBA Finals earlier this month as they fell to a 4-1 series defeat to the San Antonio Spurs.