Abstract: The present invention discloses a method and a communication device for assigning a scheduling grant. The method for assigning a scheduling grant includes: receiving a grant value, an E-TFCI offset value, and a data stream identifier corresponding to the E-TFCI offset value, where the E-TFCI offset value is determined by the Node B according to data transmitted by a mobile terminal through two data streams; determining, according to the grant value, a transport block size of the data stream identified by the data stream identifier in a current TTI; and determining a transport block size of the other data stream in the current TTI according to the transport block size and the E-TFCI offset value. in the embodiments of the present invention the MIMO technology may be applied to the HSUPA technology.