A connecting system of a multi-section housing provided at one end face of a first and second housing superposed with their display surfaces at the outsides, comprising: a first shaft vertical to superposed surfaces of first and second housing; and a second shaft perpendicular to the first shaft, wherein if a center line of the first shaft is arranged on a line bisecting the end face to the left and right and the center line of the second shaft is arranged on the superposed surfaces of the first and second housing, the first shaft can be used to allow the second housing superposed over the first housing to be rotated by 180 degrees and, in this state, the first housing can be made to rotate by the second shaft by 180 degrees so as to arrange the display surfaces of the first and second housings on the same plane.