A pot experiment was conducted to evaluate the effects of 5 different potassium(K)fertilizers \[potassium mineral(K1),citratesoluble potassium fertilizer(K2),citratesoluble potassium fertilizer containing 25% watersoluble potassium(K3),citratesoluble potassium fertilizer containing 50% watersoluble potassium(K4)and potassium sulphate(K5) at rate of K2O 150 mg/kg\],and different application rates(05K2,K2,15K2 and 2K2 at rates of K2O 75,150,225 and 300 mg/kg,respectively)and combined application(0.5K2+0.5K5)on rice biomass,K uptake and soil available K(SAK)concentration.The results indicated that K application significantly increased rice biomass,K uptake and SAK except for K1 as compared with no K application treatment.Under same K application rate,rice biomass,K uptake and SAK markedly increased and then decreased with watersoluble potassium concentration increasing in citratesoluble potassium fertilizer,and the highest values in rice biomass,K uptake and SAK were occurred in K4(240.90 g/pot,2.60 g/pot and 75.4 mg/kg)and K3(234.86 g/pot,2.24 g/pot and 73.9 mg/kg,respectively)treatments.Compared with K5 treatment,K4 and K3 treatments both significantly increased rice biomass,K uptake and SAK by 9.35% and 6.61%,40.43% and 21.26%,22.01% and 19.58%,respectively.Rice biomass,K uptake and SAK significantly increased with K2 application rate increasing and the highest values were observed in 2K2 treatment.The results demonstrated that citratesoluble potassium fertilizer containing 25%～50% watersoluble potassium(K4 and K3)had the best effect in increasing rice growth;citratesoluble potassium fertilizer(K2)had same effect at 2fold K application rate as compared with K4 and K3.