This paper presents a flying display system using an autonomous blimp (small indoor airship) with a visual tracking system and an image projection system. The real-time visual tracking system tracks the blimp while it flies along a given spatial path to follow a wall. The image projection system projects still images or a video stream, whose rectangular shape is pre-compensated to look natural and flat using a an image warping algorithm, on the surface of the blimp. The blimp is designed to have holonomic dynamics and it can maintain a stable pose and position in the presence of bounded air flow disturbances during the wall following motion. The real-time visual tracking system tracks the blimp and calculates its position in three dimensional space. Finally, we verify the capability of the autonomous blimp, the real-time visual tracking and the image projection system by experiments in the public exhibition environment. We also verify that the system is useful for transferring information and advertising in a crowded public area such as an exhibition hall or a department store.