Field experiments were conducted to study the control efficiencies of fungicides to rice blast and sheath blight under water direct seeding in Heilongjiang Province. The main results indicated as follow. The best fungicide of control leaf blast and neck blast were all 40% isoprothiolane WP, which the control effect were 77.33% and 89.98%, respectively. Furthermore, the yield of rice was 7.93 t/ha and 7.69 t/ha, respectively. The best fungicide of control sheath blight was 24% thifluzamide SC, which the control effect was 88.14%. Furthermore, the yield of rice was 7.98 t/ha. The best fungicide of concurrent control neck blast and sheath blight was 27% tebuconazole · benziothiazolinone, which the yield of rice was 7.36 t/ha, and the yield increased 36.04% than the control. The hazard weight of rice diseases may be neck blast ＞ leaf blast ＞ sheath blight under this test condition.