A support plate includes a plate body, which has a shape of a flat plate with predetermined width and length and made of metal, and a radio coverage area member, which is provided at one of opposite ends of the plate body so as to be located adjacent to a radio coverage area of an antenna and made of plastic. Further, a mobile communication terminal has the support plate that supports a mobile communication terminal body on which at least one antenna is installed and transmits and receives radio waves through the antenna.