A valve timing control device includes a rotor fixed on a cam shaft, a housing member rotatably mounted on the cam shaft so as to surround the rotor, a chamber defined between the housing member and the rotor and having a pair of circumferentially opposed walls, a vane mounted on the rotor and extended outwardly therefrom in the radial direction into the chamber so as to divide each of chamber into a first pressure chamber and a second pressure chamber, a fluid supplying device for supplying fluid under pressure to at least a selected one of the first pressure chamber and the second pressure chamber, a locking mechanism for connecting the housing member and the rotor and a canceling device for canceling the locking mechanism and for keeping the locking mechanism canceling by the fluid pressure of the fluid supplying device.