Mills Watson nació el 10 de julio de 1940 en Oakland, California, Estados Unidos. Es un actor, conocido por Cujo (1983), Up in Smoke (1978) y Papillón (1973). Está casado con Sue. Ha estado casado con Caroline Mary Mason.
When asked in an interview if he missed acting, he replied: "No. I was very fortunate to have been able to do as much as I wanted. I did enough of that. Today I have a fifteen-acre farm, growing hay. I just relax here with Sue. There's no pressure up here in Oregon. It's safe and it's not stressful at all, which I feel is keeping me alive.