The application discloses an activation method of a secondary cell. The activation method includes the following steps: when system information change happens in a secondary cell (SCell) of UE and corresponding processing operations are completed, if the current service quantity of the UE is larger than a preset service quantity threshold and before the system information is changed, the SCell of the UE is at an activation state, a base station activates the SCell of the UE; and when the UE completes a switching process, if before the switching, an SCell at an activation state exists in the UE, the base station triggers the current SCell of the UE so as to carry out activation. Through adoption of the activation method of the secondary cell, a problem that user service continuity is affected when system information change of the SCell of the UE happens and switching happens can be effectively solved.