Abstract: [Objective] The purpose of this study is to determine the effects of potassium application and foliar application of gibberellin on grain filling and yield of spring wheat.[Method]The wheat variety Xinchun-31 was selected and applied with potassium fertilizer at jointing stage, and gibberellin was sprayed at the flowering stage to study its effect on grain dry matter accumulation, yield composition and yield.[Result]The results showed that the grain filling process of wheat presented the "S" curve trend.The dry matter accumulation of the seeds showed that K180> K360> K0.And they both reached its maximum 30 days after its anthesis.Under the same level of potassium fertilizer application, with the increase of gibberellin concentration, theoretical maximum grain weight, average grain filling rate, maximum grain filling rate and grain yield increased, and reached its maximum at GA4 level.With the increase of the potassium fertilizer application, the yield of the wheat increased significantly, which presented K180> K360> K0, and reached its highest at K180.[Conclusion]In the combination of 180 kg/hm2 of potassium fertilizer and foliar spraying gibberellin concentration of about 24 g/hm2, it was most beneficial to the efficient production of Wheat.