Methods and mobile communication devices for reporting an MDT log are provided. The method is used in a mobile communication device in a service network comprising a plurality of cells. The method comprises transmitting, by the mobile communication device, an MDT log to the service network via a serving cell upon receiving a request message for the MDT log; and terminating, by the mobile communication device, the transmission of the MDT log in response to a change of the serving cell from a first cell to a second cell in the service network.