Embodiments of the present application provide a wireless communication method and device, able to improve communication performance and avoid damages to terminal hardware. The method comprises: a terminal device sending a first message to an access network device, the first message being used for carrying first capacity information and/or first function parameter information, the first capacity information being used for instructing the access network device to update the maximum communication capacity of the terminal device to a first communication capacity, the first function parameter information being used for instructing the access network device to update the function parameter or parameter range of the terminal device for communication to a first function parameter or parameter range; and the terminal device receiving a second message sent by the access network device, the second message carrying the function parameter or parameter range configured by the access network devicefor the terminal device according to the first capacity information and/or the first function parameter information.