A method for controlling a BWP inactivity timer, wherein the method is applied to a terminal device, and comprises: in a case where there is at least one configured or activated bandwidth part, BWP, for the terminal device, controlling a BWP inactivity timer of each BWP in the at least one configured or activated BWP according to a preset processing mode or a network configuration mode, wherein the preset processing mode or the network configuration mode is a way in which the BWP inactivity timer is processed or configured, including that the BWP inactivity timer is started, or the BWP inactivity timer is restarted, or the BWP inactivity timer is not started, or the BWP inactivity timer is stopped; and the method is characterized in that the at least one configured or activated BWP for the terminal device includes multiple activated BWPs for the terminal device; the controlling a BWP inactivity timer of each BWP in the at least one configured or activated BWP according to the preset processing mode or the network configuration mode, includes: in a case where the terminal device initiates random access on a first BWP and receives a random access response on a second BWP, and a BWP inactivity timer of the second BWP has been started or restarted, stopping the BWP inactivity timer of the second BWP; wherein the first BWP and the second BWP are both BWPs in the at least one configured or activated BWP, and the first BWP and the second BWP are different BWPs; or, in a case where the terminal device initiates random access on a first BWP and receives a random access response on a second BWP, stopping BWP inactivity timers of all BWPs in a cell to which the second BWP belongs; wherein the first BWP and the second BWP are both BWPs in the at least one configured or activated BWP, and the first BWP and the second BWP are different BWPs. in a case where there is at least one configured or activated bandwidth part, BWP, for the terminal device, controlling a BWP inactivity timer of each BWP in the at least one configured or activated BWP according to a preset processing mode or a network configuration mode, wherein the preset processing mode or the network configuration mode is a way in which the BWP inactivity timer is processed or configured, including that the BWP inactivity timer is started, or the BWP inactivity timer is restarted, or the BWP inactivity timer is not started, or the BWP inactivity timer is stopped; and the method is characterized in that the at least one configured or activated BWP for the terminal device includes multiple activated BWPs for the terminal device; the controlling a BWP inactivity timer of each BWP in the at least one configured or activated BWP according to the preset processing mode or the network configuration mode, includes: in a case where the terminal device initiates random access on a first BWP and receives a random access response on a second BWP, and a BWP inactivity timer of the second BWP has been started or restarted, stopping the BWP inactivity timer of the second BWP; wherein the first BWP and the second BWP are both BWPs in the at least one configured or activated BWP, and the first BWP and the second BWP are different BWPs; or, in a case where the terminal device initiates random access on a first BWP and receives a random access response on a second BWP, stopping BWP inactivity timers of all BWPs in a cell to which the second BWP belongs; wherein the first BWP and the second BWP are both BWPs in the at least one configured or activated BWP, and the first BWP and the second BWP are different BWPs. in a case where the terminal device initiates random access on a first BWP and receives a random access response on a second BWP, and a BWP inactivity timer of the second BWP has been started or restarted, stopping the BWP inactivity timer of the second BWP; wherein the first BWP and the second BWP are both BWPs in the at least one configured or activated BWP, and the first BWP and the second BWP are different BWPs; or, in a case where the terminal device initiates random access on a first BWP and receives a random access response on a second BWP, stopping BWP inactivity timers of all BWPs in a cell to which the second BWP belongs; wherein the first BWP and the second BWP are both BWPs in the at least one configured or activated BWP, and the first BWP and the second BWP are different BWPs.