The present invention relates to a method and device for operating a terminal in a wireless communication system. According to the present invention, downlink control information is transmitted to a terminal and can include symbol information related to the last symbol of a downlink shared channel. A method and device can be provided wherein a terminal transmits a first demodulation reference signal(DMSR) and at least one second DMRS for demodulating downlink data, and transmits data through the downlink shared channel, and a symbol position to which the at least one second DMRS is mapped is determined according to the symbol information.