Abstract: In order to explore the therapeutic effect of Eupatorium fortunei Turcz extract on piglet white diarrhoea, and its effect on piglet production performance, the test selected 125 about 21-day-old sick pigs naturally infected with piglet white diarrhoea, which were randomly divided according to natural nest, age, weight and other indexes into Eupatorium fortunei Turcz high（3 g/kg）,medium（2 g/kg）,low（1 g/kg） dose groups, Chinese pulsatilla powder group（drug control group）,positive control group, another 30 healthy piglets as blank control group. Continuous medication for 5 days was carried out; the mental state, appetite and faeces condition of the test pig were observed and recorded, and the average gain and feed intake were measured, and the cure rate and efficiency of Eupatorium fortunei Turcz extract against piglet white diarrhoea were calculated. The results showed that the weights of Eupatorium fortunei Turcz high, medium, low dose groups were significantly higher than that of positive control group（P＜0.05）;the effect of Eupatorium fortunei Turcz medium dose group was the best, significantly higher than Eupatorium fortunei Turcz low dose group, drug control group, blank control group（P＜0.05）;the faeces scores of Eupatorium fortunei Turcz high, medium, low dose groups were extremely significantly lower than that of positive control group（P＜0.01）,and had no significant difference with blank control group（P＞0.05）. The cure rates of Eupatorium fortunei Turcz high, medium, low dose groups were 86.67%,93.33%,80.00%,which were extremely significantly higher than the cure rate 20.00% of positive control group（P＜0.01）,and the efficiencies were 96.67%,100%,93.33%. The results suggested that Eupatorium fortunei Turcz extract had a good treatment and weight gain effect on sick pigs naturally infected with piglet white diarrhoea; the effect of Eupatorium fortunei Turcz medium dose was the best.