In order to explore the effects of straw potassium combined with chemical potassium on potatoyield，qualityand soil potassium balance in centralGuizhou，and provide scientific basis for rational utilization of straw and potassiumfertilizer resources in central Guizhou，using potato Xuanshu No.2 as the test crop，five treatments were setup:nopotassium fertilizer(NP)，chemical potassium fertilizer(NPK)，straw potassium fertilizer(S)，chemical potassiumfertilizer+straw potassium fertilizer(NPKS)，chemical potassium fertilizer(NPK1).The results showed that under theconditions with sufficient nitrogen and phosphorusnutrients，chemical potassium combined with strawpotassium，strawpotassium and chemical potassium had obvious effect on yield comparedwith(NP)，which wasNPKS>NPK1>NPK>S>NP，and the effect of combined application of straw potassium and chemical potassium fertilizer was thebest.With the increaseof planting years，the coefficient of variation of yield between years was slight，which was conducive to stable yield.Thestarch and Vc content increased with potassium content，but the content of raw sugar and nitratedecreased.The treatment of chemical potassium fertilizer and straw potassium had similar trend in nutrient uptake and quality under high and lowpotassiumconditions，while potassium uptake and Vc content had significantdifference.The apparent profit and loss of soil potassium showed that the potato growth could be satisfied when the soil potassium content was 129.2 kg/hm².Therefore，under the condition of highpotassium，the apparent equilibrium coefficients of potassium inNPKS，NPK1，NPK and Streatments were1.36，1.51，0.65 and0.63，respectively.In summary，on the basis of adequate application of nitrogenand phosphorusfertilizers，the combination of straw potassium and chemical potassiumfertilizer(225 kg/hm²)significantlyincreased potatoyield，quality and nutrientuptake.It was conducive to the balance of soil potassium，reduced potatodepletion of soil potassium，and maintained the stability of soil potassium fertility，while it reduced the yield variations caused by climatic factors and improved the stability of yield.