Depends on how strong you think He-Man is and/or what version you are going with. I am most familiar with the cartoon version from the 80's. Going by that depiction, I don't remember him being shown as definitively stronger than Hercules, but I could be wrong.
Hercules has been at it for far longer than He-Man and is probably a better fighter.
He-Man would have to have a serious strength and/or durability advantage to beat Hercules. In my opinion.
He Man seems to be able to battle Supes in vrute strenght pretty well!