Using the grape variety‘Cabernet Sauvignon’as test material, conditions for Plasmopara viticola sporan-gium formation were studied. The results showed that the germination rate of sporangia in suitable conditions for 8hcould reach more than 80%, and optimal germination temperature was 10~25℃. Alternating light and dark environ-ment could accelerate the sporangia germination, but light intensity had little effect on the germination.