Abstract: The control effect of 11 fungicides against Diplocarpon mali were tested on Malus robusta Rehd seedlings and Fuji apple trees by applying the fungicides after inoculating the pathogen to the hosts. Four fungicides, the mixture of tebuconazole and SYP-1620, flusilazole, propiconazole and prochloraz showed significant control effect against Diplocarpon mali. Other 4, difenoconazole, polyoxin, thiophanatemethyl and SYP-1620 also showed control effect, but the efficiency was not effectively. Whereas, the other 3, pyraclostrobin, the mixture of pyraclostrobin and metiram and carbendazim did not show any control effect. The effective applying time of the 4 fungicides, the mixture of tebuconazole and SYP-1620, flusilazole, propiconazole and prochloraz, to control the disease were also examined. Results indicated that the 4 fungicides would inhibit the appearance of lesions when applied before the disease show symptoms. The more effective the control efficiency of the 4 fungicides, the earlier when they were applied. The mean control effect of 4 fungicides was 96% when applied at the third day after inoculation. However, the control effect dropped to 77% when applied at the fifth day after inoculation. When applied on the early stage of the disease show symptom, the 4 fungicides could inhibit expansion and sporulation of the lesions. Whiles, when applied before sporulation, they could inhibit the sporulation of the lesions. The results indicate that the effective applying time for the system fungicides to control Diplocarpon mali is within 1 week after infection of the pathogen on apple orchards.