Abstract: In order to screen high efficiency and low toxicity botanical fungicides for against the black scurf and early blight of potato, reduce the effective dosage and improve the control effect, the mycelium growth rate method was used to test the toxicity of botanical fungicides eugenol and matrine, and using fludioxonil and mancozeb as the control.The results showed that both two botanical fungicides had better effect on inhibiting the growth of two pathogens, and the EC₅₀ values of 1.1% eugenol and 1.5% matrine were 2.101 4 and 2.442 1 mg·L^-1 for black scurf and 0.761 0 and 0.875 2 mg·L^-1 for early blight, respectively.The significance analysis showed that the inhibition effect of 1.1% eugenol and 1.5% matrine was not significant, but compared with the control chemicals, both showed significant differences.The results indicated that the two botanical fungicides had better indoor inhibition effects than the conventional chemicals for the control of pathogens.