Abstract: In order to find out effective fungicides against Alternaria alternata, the indoor toxicity and field control effects of 7 fungicides against Alternaria alternata were studied with the method of mycelium growth inhibition. The results of indoor experiments showed that tebuconazole 43% SC presented the highest virulent with the lowest EC₅₀, 0.0018 mg/mL;the EC₅₀ of Iprodione 75% WP, dimethachlon 40% WP, kangchixing No.1 45% WP, polyoxin 3% WP, mancozeb 80%WP and Thiophanate methyl 70%WP were 0.0063, 0.1597, 0.1891, 0.3835, 1.755 and 9.1313 mg/mL, respectively. The results of field experiments showed that tebuconazole 43% SC (diluted to 1/2000) exhibited the best contro1 effect. Seven fungicides in the order of control effect were tebuconazole 43% SC (diluted to 1/2000)>dimethacholn 40% WP (diluted to 1/600)>Iprodione 75% WP (diluted to 1/600)>polyoxin 3% WP (diluted to 1/500)>kangchixing No.1 45% WP (diluted to 1/800)>mancozeb 80% WP (diluted to 1/500)>Thiophanate methyl 70% WP (diluted to 1/700).