A method of restricting a measurement reporting, which is restricted by a user equipment in a mobile communication system, comprising the steps of: receiving (S1510, S1610) a cell list including information on a plurality of cells from a serving cell; receiving (S1520, S1620) a measurement configuration message from the serving cell, the measurement configuration message comprising: a plurality of measurement objects, a plurality of reporting configurations each of which includes a reporting condition and a reporting type, and a measurement identity to be used for connecting each of the plurality of measurement objects and each of the plurality of the reporting configurations; receiving (S1520, S1620) a measurement configuration change message from the serving cell; measuring (S1530, S1630) qualities of signals received from two or more cells in accordance with the measurement configuration message and the measurement configuration change message; performing (S1540, S1640) a measurement evaluation to determine whether to make a quality measurement report that is based on the measured qualities of the signals received from the two or more cells; and based on the measurement evaluation, transmitting to the serving cell a measurement reporting message including measurement reporting information that is based on the measured qualities of the signals received from the two or more cells, characterized in that the two or more cells are included in the cell list and are able to be serving cells when carrier aggregation, CA, is configured for the user equipment, and that the measurement configuration change message instructs the user equipment to restrict measurement objects to the two or more cells which are able to be the serving cells. receiving (S1510, S1610) a cell list including information on a plurality of cells from a serving cell; receiving (S1520, S1620) a measurement configuration message from the serving cell, the measurement configuration message comprising: a plurality of measurement objects, a plurality of reporting configurations each of which includes a reporting condition and a reporting type, and a measurement identity to be used for connecting each of the plurality of measurement objects and each of the plurality of the reporting configurations; a plurality of measurement objects, a plurality of reporting configurations each of which includes a reporting condition and a reporting type, and a measurement identity to be used for connecting each of the plurality of measurement objects and each of the plurality of the reporting configurations; receiving (S1520, S1620) a measurement configuration change message from the serving cell; measuring (S1530, S1630) qualities of signals received from two or more cells in accordance with the measurement configuration message and the measurement configuration change message; performing (S1540, S1640) a measurement evaluation to determine whether to make a quality measurement report that is based on the measured qualities of the signals received from the two or more cells; and based on the measurement evaluation, transmitting to the serving cell a measurement reporting message including measurement reporting information that is based on the measured qualities of the signals received from the two or more cells, characterized in that the two or more cells are included in the cell list and are able to be serving cells when carrier aggregation, CA, is configured for the user equipment, and that the measurement configuration change message instructs the user equipment to restrict measurement objects to the two or more cells which are able to be the serving cells.