A refrigerator includes a main body defining a storage compartment, a door, an ice making device, a water tank disposed for supplying water into the ice making device, and an ice bin to receive and store ice pieces made in the ice making device. The ice making device includes an ice making tray having ice making chambers configured to be filled with water for making the ice pieces, and an ejector extending from an upper central portion of the ice making tray in a longitudinal direction of the ice making tray to pass through both ends of the ice making tray. The ejector is configured to be maintained in a fixed state during water supply, ice making, and ice separation processes, and the ice making tray is configured to rotate at an angle of about 360° in one direction with respect to the ejector.