Portable telephone apparatus including electronic notebook function

In a portable telephone apparatus equipped with an electronic notebook function, a telephone operation key such as a dialing key is mounted on an upper surface of an openable/closable member mounted on an upper surface of a case body, whereas electronic notebook operation keys such as a character input key are provided at a region of a surface of the case body covered by the openable/closable member, and also at a rear surface of the openable/closable member. The portable telephone apparatus further includes a switch for detecting an opening/closing state of the openable/closable member, and a mode selecting unit for selecting a telephone mode and an electronic notebook mode in response to a detection signal derived from the detecting signal. Furthermore, a search key for searching storage data about the electronic notebook is employed on this upper surface of the openable/closable member. When this search key is operated, electronic notebook data such as telephone directory data constructed of one pair of a telephone number and a name, may be displayed on a display unit.