A field experiment was conducted with 6 potassium fulvic acid application rates:FA1(0 kg/hm²)，FA2(45 kg/hm²)，FA3(75 kg/hm²)，FA4(105 kg/hm²)，FA5(135 kg/hm²)and FA6(165 kg/hm²)to explore the effects of potassium fulvic acid application on melon growth and biomass accumulation，nutrients uptake. The results indicated that the application of potassium fulvic acid promoted the biomass accumulation，enhanced the absorption of nitrogen，phosphorus，potassium in root，stem(leaf)and fruit. In addition，the soluble solid and yield of melon was also improved with higher potassium fulvic acid application. The biomass in different parts，the nutrients uptake as well as the economic yield was the highest when the potassium fulvic acid application rate reached to 135 kg/hm². Compared with FA1 treatment，the dry biomass and nitrogen，phosphorus，potassium accumulation of FA5 in root，stem(leaf)and fruit significantly increased by 17.42%，30.74%，43.96%；52.29%，56.10%，99.30%；76.32%，78.82%，129.23% and 37.47%，43.97%，88.36%；respectively，at the mature stage of melon. In addition to the FA2 treatment，the single fruit weight，economic yield and soluble solid content of BSFA applied treatments were 7.60%～22.81%，8.01%～22.85% and 7.85%～17.89%，7.90%～9.58% higher than those of FA1 treatment. No significant difference in yield and quality of melon between FA5 and FA6 treatment was observed，but they were higher than other treatments. In conclusion，high application of potassium fulvic acid was more conductive to the high yield and quality of melon，but excessive application (> 135 kg/hm²)could actually cause fertilizer waste. Therefore，the application rate of potassium fulvic acid application at 135 kg/hm² is the optimal measure for melon growth in this experiment condition.