Neal, 26, and in his sixth NHL season, struck Boston's Brad Marchand with his knee after Marchand had fallen to the ice and was trying to get up midway through the first period.
Neal was given a two-minute penalty for kneeing by game officials. The league followed Monday with a phone hearing and five-game suspension assessment. Neal is eligible to return to the ice for the Penguins' Dec. 19.
The incident also led to a fight in which Boston's Shawn Thornton hit Pittsburgh's Brooks Orpik twice. Orpik was taken from the ice on a stretcher and spent a night in a hospital. He has been placed on injured reserve with a concussion.
Thornton was given a match penalty and could be facing league disciplinary action.
Boston won the game 3-2.