A method and system for indicating a transmission parameter are provided in the present invention. The method includes: when multi-user multi-input multi-output (MIMO) data are transmitted, using a newly-added indication signaling in a downlink control information format to indicate different joint encoded parameters when numbers of enabled transport blocks are different. Through adding new indication signaling in the present invention, different joint encoded parameters are indicated during the multi-user MIMO data transmission and the MIMO multi-user transmission based on the demodulation reference signal is supported.