In order to improve the communication performance of Computational Radio Frequency Identification(CRFID) system, a fast response scheme and a data retransmission mechanism were proposed. Aiming at the issue of communication failure caused by the slow response rate of CRFID tags to readers, the use of pre-calculated RN16 and fixed tag handle methods simplifies the communication process and improves the response rate of tags. For the issue of low efficiency and high energy consumption of CRFID tag data retransmission, the data format combining tag data and data address is used for transmission. The reader can accurately locate the error data and re-request tag data through the address of the error data, which improves the success rate of bulk data transmission and reduces the energy consumption for retransmiting errors data. Finally, through experimental verification, it can be known that the scheme improves the communication performance of the passive CRFID system.