Field experiments were carried out to study the effects of Kbearing materials（i.e.straw，straw ash，SiCaK fertilizer，citrate acidsoluble potassium fertilizer，and KCl）on the seed yield and potassium accumulation of winter oilseed rape.The results showed that application of Kbearing material fertilizer at the rate of K2O 120 kg/hm2 significantly increased the yield and potassium accumulation of rapeseed.The seed yield increased by 14.5%~34.9%，while the potassium accumulationof shoot increased by 71.8%~143.0%.However，application effect of different Kbearing materials varied，the treatment of citrate acidsoluble potassium fertilizer was the best，followed by the straw ash and KCl treatment compared with CK treatment.Additionally，potassium use efficiency in treatments of the citrate acidsoluble potassium fertilizer，straw ash and KCl treatments was significant higher than those of SiCaK fertilizer and straw.Besides，effects of the type of Kbearing materials on soil potassium supply were different，the KCl treatment and straw ash treatment had the higher soil available K and citrate acidsoluble potassium fertilizer had the higher soil slowly available K than the others after the oilseed rape harvest significantly.The results showed that the straw ash and citrate acidsoluble potassium fertilizer had the same effect of application with potassium chloride under the same potassium nutrient supply.