What was the first Pokémon video game to use three-dimensional Pokémon models?

Pocket Monsters Stadium was the first Pokémon video game to use three-dimensional Pokémon models.

Nintendo released Pocket Monsters Stadium in Japan for the Nintendo 64 on August 1, 1998. The game presented battles with polygonal Pokémon models and included an announcer, tournament modes, multiplayer battles, and connectivity with the Game Boy games through the Transfer Pak.

Although its English title is often rendered as Pokémon Stadium, the Japanese release is a distinct early game. It was not released outside Japan. A more expansive follow-up was later localized internationally as Pokémon Stadium, which can cause confusion when people identify the first 3D Pokémon title.

Technical limitations meant that only 40 Pokémon could be used in battles in the Japanese game, even though its encyclopedia could display all 151 first-generation species. The title helped establish Pokémon’s transition from handheld sprites to console-based 3D presentation.