Haggerty died Friday morning in a Burbank, California, hospital surrounded by his family, said his manager, Terry Bomar.
With his long hair, full beard and 6-foot-1 build, Haggerty seemed born to play Adams, who was based on a 19th-century frontiersman.
Haggerty said he got the job after another actor didn’t work out.
A producer saw him in a movie and asked his secretary – who happened to be Haggerty’s wife – if he was available.
How would you like to be Grizzly Adams?” Haggerty recalled.
Haggerty started his career in beach pictures and biker flicks.