Transcription activator CBF1 is a trans-activating factor in arabidopsis, which can be induced by low temperature. The CBF1 gene is cloned, which is derived from Arabidopsis with PCR. Then CBF1 cDNA and plant expression vector pBI121 are conjugated to construct the recombinant plasmid pBI121-CBF1. With agrobacteriummediated transgene technique, the authors successfully introduce the arabidopsis transcriptional factor gene CBF1 into hybrid pennisetum, and reproduce the transgenic hybrid pennisetum.