Mourning had said before the season this would be his last but the campaign came to a premature end December 19 when he tore the patella tendon and quadriceps tendon in his right knee.
The injury came as Mourning ran down the court and landed under the rim to position himself to block a shot in the first quarter of an eventual 117-111 Miami overtime loss to Atlanta.
Mourning underwent surgery but an announcement on the Heat web site Monday seemed to indicate he was finished.
"I'm retired. This is it for me," Mourning said. "There's a possibility that I can explore some coaching opportunities if at the particular time I'm in the right frame of mind."
The two-time NBA Defensive Player of the Year had already defied Father Time just by lasting this long, becoming the first player in US sport to take the court following a kidney transplant.
Mourning suffered from a rare kidney disease and stepped away from the game after the 2003 diagnosis but returned for the 2004-2005 season after the transplant.
Mourning averaged 17.1 points and 8.5 rebounds a game over 837 NBA appearances for Miami, the Charlotte Hornets and New Jersey after being taken second overall in the 1992 NBA Draft.
His only NBA title came in 2006 with the Heat.kaynak : NBA