The present invention relates to a wireless communication system. More particularly, the present invention relates to a signal transmission method in which a terminal transmits a signal in a wireless communication system, said method comprising the steps of: checking the maximum transmission power (P_CC_MAX) for each component carrier of a plurality of component carriers, as well as the maximum transmission power (P_UE_MAX) of the terminal; calculating the transmission power for each channel to be simultaneously transmitted to a base station through one or more component carriers; independently adjusting the transmission power for each of the channels so as not to exceed the maximum transmission power (P_CC_MAX) and the maximum transmission power (P_UE_MAX); and transmitting a signal to the base station through the plurality of channels for which the transmission power is adjusted.