A routing device and a signal transmitting method for a Wireless Local Area Network (WLAN) are provided. The device includes: a radio frequency transmitting module, adapted to: generate radio network signals of the WLAN, and adjust the transmit power of the radio network signals according to power indication information; and an antenna module, adapted to transmit the radio network signals according to the adjusted transmit power. The method includes: generating radio network signals of the WLAN, and adjusting the transmit power of the radio network signals according to power indication information; and transmitting the radio network signals according to the adjusted transmit power. Through the routing device and the signal transmitting method, the radio network signals may be transmitted according to different transmit powers. Therefore, the routing device can meet the requirement for portability, fixed installation, and wide coverage.