A Mega Stone (Japanese: メガストーン Mega Stone) is a type of held item introduced in Pokéemon X and Y. It allows Pokémon to Mega Evolve.

Mega Stones in Pokémon X and Y are only used during battle so the player can use their Mega Ring to Mega Evolve a Pokémon if it is holding the correct Mega Stone before it attacks. Mega Stones now last as long as a pokemon holds it's correct stone Pokémon during battles. All Pokémon that can undergo Mega Evolution have an equivalent Mega Stone that is named after them.

Mega Stones, can't be taken awa y bby the use of a ability or move, and fail if used by the holder, and Mega Stones are not consumed upon use.