An electrically erasable and programmable read only memory (EEPROM) device and a method of manufacturing the EEPROM device are provided. First and second gate structures having the same structure are formed on a tunnel insulating layer formed on a substrate, such that the first and second gate structures are spaced apart from each other. A common source region is formed at a portion of the substrate located between the first and second gate structures. First and second drain regions are formed at first and second portions of the substrate adjacent to the first and second gate structures, respectively. Thus, the EEPROM device is manufactured including first and second transistors that have the same structure and may alternately serve as a memory transistor and a selection transistor according to an applied signal.