The present invention discloses a gain adjustment method for wireless communication. This method is carried out by a wireless transceiver, and an embodiment of the method comprises the following steps: obtaining at least one transceiving parameter of a wireless connection partner; determining an adaptive power gain according to the at least one transceiving parameter; having an idle power gain of a radio-frequency circuit of the wireless transceiver be the adaptive power gain for a period of time, or having the idle power gain of the radio-frequency circuit be the adaptive power gain until packet transmission operation or packet reception operation takes place within the period of time; and if none of the packet transmission operation and the packet reception operation takes place within the period of time, having the idle power gain of the radio-frequency circuit be an initial power gain right after the period of time.