Sackboy is a fictional character and main protagonist of the LittleBigPlanet video game series published by Sony Interactive Entertainment. Introduced in the 2008 video game LittleBigPlanet, Sackboy is a small, anthropomorphic, humanoid doll-like character made of burlap sack with a brown knit pattern by default, with a zip fastener and button eyes. Sackboy was originally designed to be a "blank canvas" for LittleBigPlanet players, and is fully customisable using costumes which are either in-game unlockable content, or purchased as downloadable content (DLC) from the PlayStation Store. Sackboy was jointly created by the founding members of British game studio Media Molecule. Scottish composer Kenneth Young provided the vocal effects for the character from 2008 to 2014.

LittleBigPlanet is a 2008 platform game developed by Media Molecule and published by Sony Computer Entertainment for the PlayStation 3, and is the first game of the LittleBigPlanet franchise. The level editor is the main focus of the game, allowing the player to create levels and publish them online. The player controls Sackboy, a customizable ragged doll with the ability to create. Story mode consists of pre-made levels built around Sackboy's basic control scheme, and they are grouped into areas, each centering around a theme; the story revolves Sackboy helping various Creator Curators around LittleBigPlanet before facing the Collector, who has been kidnapping and stealing creations.