The effects of potassium fertilizer on the character of overwintering and agronomic characters of winter wheat were studied by using different treatments of potassium.The results showed that the rate of overwintering raised with the increase of amount of potassium applied.The cold resistance was improved and the winter wheat could overwinter safely through increase of amount of potassium applied.The differences among different treatments were significant on the spikelet number of main spike,the valid spikelet number,the seed weight of single plant and the plot yield.