For others with the same name, see: John Green (disambiguation).

John Green, referred to by friends and supporters as "Mr. Sasquatch," is a leading researcher into the bigfoot phenomenon.

A journalist by training, he has collected more than 3000 sighting reports. He is the author of . The character played by Don Ameche in the 1987 movie Harry and the Hendersons is loosely modeled after Green.