Disclosed is a rotary type hinge device, which is rotatably coupled to a portable wireless terminal, especially to a body of the folder type terminal. The hinge device includes a first rotation axis for opening and closing operations of the terminal body and folder, and a second rotation axis extending perpendicular to the first rotation axis, thereby causing the folder to rotate about the second rotation axis in its opened state. By providing the hinge device of biaxial rotation type constructed as stated above, limitations in installation positions of a display device and camera lens can be removed, thereby improving the compatibility of the portable wireless terminal with respect to motion picture providing services, video communications and so on, so that it provides diversified mobile communication services. Further, the design and specification of the portable wireless terminal can be easily changed. Furthermore, the convenience in use of the portable wireless terminal can be increased since there is little variation in the opening and closing state of the portable wireless terminal whether the terminal is used as a phone mode or PDA mode.