A mobile communication method includes the steps of transmitting a first control signal including an identifier different from a C-RNTI to the mobile station UE#A through a PDCCH by a radio base station PhNB#10 managing a cell #10 formed by linking multiple small cells, transmitting a second control signal including an identifier to the mobile station UE through a PDCCH by a radio base station eNB#1 managing a cell #1 having a coverage area overlapping with a coverage area of the cell #10, and regarding the first control signal as valid by the mobile station UE#A, when it determines that the identifier included in the first control signal and the identifier included in the second control signal match each other.