Abstract: The mechanism for containing an input pen is provided with a pen holder having a shape of pipe, which contains an input pen having substantially a shape of stick, keeping the back end of the input pen exposed. The pen holder is provided with a pen stopper to couple with the input pen. There is provided a locking groove which is coupled with the pen stopper. There is provided a plate spring which supplies force to the pen stopper to the inside of the pen holder. At least one of the pen stopper and the locking groove is so shaped that the pen stopper is supplied force against the force of the plate spring when the input pen is supplied force in the discharge direction. In this arrangement, the mechanism for containing an input pen can be made simpler since the input pen can be taken out without a releasing button conventionally needed. Therefore, since the number of parts and the number of manufacturing procedures in assembly decrease, manufacturing cost can be reduced.