that will kill arabbit, squirrel, groundhog, gopher, robin, chipmunk, and turkey among others.so yes, it will in fact kill a squirrel. assuming you make good shots to the upper torso/head area. i doubt that would kill a squirrel if shot in the rear.there are those freak instances where something doesn't go right. i've shot a chipmunk from 5 yards away in the side of the head with a .22 and had it RUN away only to be shot in the heart and continue to limp away. after that i shot it in the back and it eventually died. just goes to show that not everything goes according to plan.