A method for wireless communication is applied to a terminal device connecting with a first network and a second network, and includes: reducing, by the terminal device when an uplink duty cycle of the second network is greater than a maximum uplink duty cycle of the second network, a power class of the first network and the second network and/or the uplink duty cycle of the second network, where the uplink duty cycle of the second network is a proportion of time domain resources that can be used for uplink transmission in a time unit, so that the electromagnetic wave SAR of the terminal device is less than or equal to a preset value.