Arthas Menethil is a fictional character who appears in the Warcraft series of video games by Blizzard Entertainment. He was once a paladin of the Silver Hand and the crown prince of Lordaeron, but he was corrupted by the cursed blade Frostmourne in a bid to save his people. He later became the Lich King, one of the most prominent antagonists in Warcraft lore. Arthas also appears as a playable character in the crossover multiplayer online battle arena game Heroes of the Storm. The critical reception of the character has been mostly positive.

In Warcraft III, Arthas is voiced by Justin Gross. In subsequent appearances, he is voiced by Patrick Seitz (paladin and death knight Arthas) and Michael McConnohie (Lich King Arthas).