PURPOSE: To provide a vane pump which enhances air-tightness, eliminates the generation of abnormal sound at the time of start, and in which a blade is not in contact with a cylinder wall.

CONSTITUTION: An outer rotor 1 is provided on the inner side of a cylinder 3, guide pins 5 which pass through a blade in play are provided in the blade provided in a pump chamber 4, and the guide pins 5 engage with a guide pin travelling groove 7 formed on the pump chamber 4 side on a side wall. Consequently, when the pump rotates, the guide pins 5 are guided by the guide pin travelling groove 7 and move, and the blade 2 is controlled in the scope of protrusion.