Field experiments were conducted to investigate the effects of potassium(K2O) levels（0,337.5,450,675,1 012.5 kg/hm2）on soil available K and nutrient absorption,potassium use efficiency and the yield of twoyearold Panax notoginseng.The results showed that the contents of available K in soil decreased gradually during the whole growth period.Compared to K0,potassium fertilizer application significantly increased the contents of available K in soil(P<005).At the same time,the contents of available K in soil increased with the rising of potassium fertilizer application amount.The accumulation amount of nitrogen,phosphorus and potassium in root of Panax notoginseng increased gradually during the whole growth period.Potassium fertilizer application obviously improved the accumulation amount of nitrogen,phosphorus and potassium at main growing stages of Panax notoginseng.The accumulation amount of nitrogen,phosphorus,potassium in overground part and root of Panax notoginseng took on a trend of increasing first and declining later with the rising of potassium application rate.K3 was the most suitable treatment to increase the accumulation amount of N,P and K of Panax notoginseng. Potassium partial factor productivity was significantly decreased with the increasing of potassium fertilizer.The plant height,leaf length,leaf width,stem diameter and biomass of Panax notoginseng increased gradually during the whole growth period.Potassium fertilizer application improved the growth of Panax notoginseng.The yield of Panax notoginseng was also significantly increased(P<0.05).Compared to the control treatment,the application of potassium fertilizer increased the yield of Panax notoginseng by 6.90%~17.17%.K3 treatment was the best treatment to increase the yield of Panax notoginseng,and K4 was ranked to be the second.Considering plant growth,nutrient absorption,potassium use efficiency and the yield of twoyearold Panax notoginsen,the optimal potassium fertilizer for Panax notoginseng was K3 treatment (K2O 675 kg/hm2).