She was best known for playing squeaky-voiced police officer Laverne Hooks in the Police Academy film franchise.
Her agency, Roger Paul Inc, told Sky News she "passed away suddenly" in the early hours of Thursday morning, but did not give a cause.
A statement confirming her death said: "Marion's passion for performing and sharing her heart with the world was immense. She carried with her a kindness and permeating light that instantly filled a room upon her arrival.
In the 80s the Police Academy films cast a long shadow over the comedy genre - they were everywhere & everyone watched them. #MarionRamsey was hilarious as Hooks - a fine comedic actress @JanineNerissa still regularly squeaks “this is a stick up!” Sorry to hear of her death at 73 pic.twitter.com/mx7SQerboL— JONATHAN SOTHCOTT (@sothcott) January 7, 2021