A folder type cellular phone and an automatic folder method includes a main body having a key pad and a hinge thereof in a first direction, a folder having a display, a driving source disposed on a lower portion of the folder in the first direction to generate a driving force, a power transmission unit having one end coupled to the driving source and the other end coupled to the folder to transmit the driving force to folder to rotate with respect to the main body when the folder is in an open state, and a rotation controller coupled to the power transmission unit and disposed in a housing installed at the hinge of the main body in a second direction perpendicular to the first direction to automatically and/or manually rotate the folder with respect to the main body.