Hulk Hogan's 65 years old and has wrestled for 4 decades ... but his son, Nick, tells TMZ Sports the WWE Hall of Famer will NEVER RETIRE from the sport he loves.
"He always says he loves it. He loves training. He loves the wrestling business. It runs too deep in his blood. I don't think he'll ever quit," Nick told us at LAX.
Of course, Hulk just made his return to WWE after being fired in 2015 ... appearing at the 'Crown Jewel' event in Saudi Arabia, and you could tell he was back in his element.