Beast King is a villain from One Punch Man. He is one of the bio-engineered members of the House of Evolution and their second strongest member according to Armored Gorilla. He is sent to capture Saitama along with the others so that he could be used on their experiments.

Beast king confronts Saitama with the help of Ground Dragon, who buries Saitama so that they could avoid a fight. Beast King threatens Saitama, who escapes from the trap and asks them to apologize. Enraged, Beast King attacks Saitama with consecutive slashes, which Saitama easily avoids. During his rampage he ends killing two of his comrades, Slugerous and Frog Man, calling them weaklings and claiming that was the law of the jungle. Beast King the powers himself up and launches an even fiercer barrage of slashes, but Saitama counters with his Normal Consecutive Punches, which instantly pulverizes Beast King.