An end-fed planar type spiral antenna for transmitting/receiving radio signals includes a spiral pattern formed to have inner and outer spiral curves turned predetermined times in a spiral shape from an arbitrary center point in a plane; a central circle pattern formed in a part of a central region of the spiral pattern in a circular shape; and a feed arm pattern formed in a rectangular shape from an end of the spiral pattern that turns predetermined times. Conductive material is patterned on a pattern where the spiral pattern, the central circle pattern and the feed arm pattern are overlapped. This antenna allows to design an antenna structure capable of effectively enhancing radiation efficiency and improving broadband characteristics by utilizing a tapered spiral structure. Also, this antenna has an improved orientation, ensures less limitation in height, and allows a small-size design.