Disclosed herein is a hinge device for a cellular phone, which has no device housing and thus, can achieve a greater slimness of the cellular phone and reduce the generation of a noise during a sliding operation of a slide body included in the cellular phone. The hinge device includes a first push rod connected to a main body of the cellular phone and having a pin and a pin hole, and a second push rod connected to a slide body of the cellular phone and having a pin and a pin hole. The pin of the first push rod is penetrated through the pin hole of the second push rod, and the pin of the second push rod is penetrated through the pin hole of the first push rod. A spring is provided around each pin.