Provided are a method and an apparatus for transmitting a signal suitable for an indoor environment. The method for transmitting a signal according to an exemplary embodiment of the present invention includes: preprocessing a signal using a signal power to sidelobe power ratio (SSR) parameter defining a signal to sidelobe ratio to minimize an inter-symbol interference and prevent performance deterioration due to reduction in signal strength; and transmitting the preprocessed signal to a receiving apparatus through a predetermined channel.