The present invention discloses a method for dynamically switching a mobile network, including: sending, by a subscription manager SM, a mobile network switch message to a first mobile network, where the mobile network switch message is used to indicate that user equipment UE needs network switching; receiving, by the SM, a notification signaling message from the first mobile network, where the notification signaling message is used to notify the SM that the UE connects to the first mobile network; and sending, by the SM, the mobile network switch message to the UE by using the first mobile network, so as to instruct the UE to switch to a second mobile network. The present invention further discloses a subscription manager and user equipment.