Marvel Legend Stan Lee's Death Certificate Lists Heart Failure as Cause of Death

Stan Lee, the creator of much of the Marvel Universe, died from heart and respiratory failure ... TMZ has learned.

We obtained Stan's death certificate, and it lists heart failure and respiratory failure as the cause of death. It also says he suffered aspiration pneumonia -- which is when you inhale food, stomach acid or saliva into your lungs. According to the document, 95-year-old Lee died Monday, November 12 at 9:17 AM at Cedars-Sinai Medical Center in Los Angeles.

TMZ broke the story ... an ambulance rushed to Lee's Hollywood Hills home earlier this month, and he was brought to Cedars-Sinai.

The certificate says he was cremated and his ashes returned to his daughter. His occupation was listed as a writer in the publishing business.

Stan was smiling and cheerful Saturday, November 10 during what would be his final sit-down with his protege, comic book writer Roy Thomas.

Stan had been battling several illnesses over the past year, including vision issues and a bout of pneumonia.

Stan launched Marvel in 1961 with the Fantastic Four and the comic book giant went on to spawn Spider-Man, The Incredible Hulk, Iron Man, X-Men, Black Panther and The Avengers.