A method of notifying resource allocation for Demodulation Reference Signal (DMRS) is provided. A base station notifies to a user equipment a power offset value between an average EPRE value for data symbols and an average EPRE value for the DMRS at each layer in a semi-static or static manner. Also, the base station dynamically notifies to the user equipment a current channel rank or a current DMRS distribution pattern for the user equipment. The user equipment determines an allocated DMRS antenna port based on a correspondence between the received channel rank and an allocation of DMRS antenna port, thereby obtaining resource allocation information for the DMRS. The signaling overhead for power allocation in the system can be reduced, the efficiency of power amplifier can be improved and the flexibility of system scheduling can be increased. A method of notifying antenna port resource allocation for DMRS is also provided.