Ico is an action-adventure game developed by Japan Studio and Team Ico, and published by Sony Computer Entertainment, released for the PlayStation 2 video game console in 2001 and 2002 in various regions. It was designed and directed by Fumito Ueda, who wanted to create a minimalist game around a "boy meets girl" concept. Originally planned for the PlayStation, Ico took approximately four years to develop. The team employed a "subtracting design" approach to reduce elements of gameplay that interfered with the game's setting and story in order to create a high level of immersion.

The protagonist is a young boy named Ico who was born with horns, which his village considers a bad omen. Warriors lock him away in an abandoned fortress. During his explorations of the fortress, Ico encounters Yorda, the daughter of the castle's Queen. The Queen plans to use Yorda's body to extend her own lifespan. Learning this, Ico seeks to escape the castle with Yorda, keeping her safe from the shadowy creatures that attempt to draw her back. Throughout the game, the player controls Ico as he explores the castle, solves puzzles and assists Yorda across obstacles.

Ico introduced several design and technical elements, including a story told with minimal dialogue, bloom lighting, and key frame animation, that have influenced subsequent games. Although not a commercial success, it was critically acclaimed for its art, original gameplay and story elements and received several awards, including "Game of the Year" nominations and three Game Developers Choice Awards. Considered a cult classic, it has been called one of the greatest video games of all time, and is often brought up in discussions about video games as an art form. It has influenced numerous video games since its release. It was rereleased in Europe in 2006 in conjunction with Shadow of the Colossus, the spiritual successor to Ico. A high-definition remaster of the game was released alongside Shadow of the Colossus for the PlayStation 3 in The Ico & Shadow of the Colossus Collection in 2011.