In response to the low temperature, plants induce relevant gene expression to increase the cold tolerance. This response is called cold acclimation. The molecular mechanism for cold acclimation has been studied, suggesting that the CBF transcription activators are critical in the signal transduction of cold acclimation. The signal pathway could be summarized as: CBF transcription factors -->CRT/DRE motif domain -->the expression of COR gene--> plant cold tolerance. Understanding the mechanism of CBF in cold tolerance will provide a new strategy for improvement of plant cold tolerance and breeding of cold-tolerant plant.