Rapeseed (Brassica napus L.) is an important oil crop worldwide, responds to vernalization, and shows an excellent tolerance to cold stresses during vegetative stage. The winter-type and semi-winter-type rapeseed were typical winter biennial plants in Europe and China. In recent years, more and more early-maturing semi-winter rapeseed varieties were planted across China. Unfortunately, the early-maturing rapeseed varieties with low cold tolerance have higher risk of freeze injury in cold winter and spring. The molecular mechanisms for coping with different low-temperature stress conditions in rapeseed recently had gained more attention and development. The present review gives an insight into the responses of early-maturing B. napus to different low-temperature stresses (chilling, freezing, cold-acclimation, and vernalization), and the strategies to improve tolerance against low-temperature stresses are also discussed.