TMZ's obtained the document, which lists Taylor's immediate cause of death as congestive heart failure. It also lists heart disease as an underlying cause.

As we reported ... Rip passed away last month in Beverly Hills. The certificate says he died at the Cedars-Sinai Medical Center.

We've also learned the famous comedian's ashes were to be scattered at sea off the coast of Honolulu ... no word if any confetti was involved.

Dubbed the "King of Camp and Confetti" and "The Crying Comedian," Rip will be remembered for his flamboyant style and appearance, countless appearances on talk shows and his brief stint hosting "The $1.98 Beauty Show."

He also guest-starred in flicks like "Wayne's World 2," "Indecent Proposal," "Tom & Jerry: The Movie," "Chatterbox!" and "Jackass 3D" ... and was a successful voice actor.

Taylor was 84.