Abstract: The test uses a single-factor repeat tests to study the effect of different irrigation patterns on the microbes in paddy soil. The result shows that the number of microbe is different under different irrigation condition. the number of Anaerobic bacteria under Flooding conditions is higher than other irrigation patterns, aerobic bacteria, fungi, actinomycetes, and the total of paddy fields soil microorganisms is the highest under shallow, wet, dry intermittent irrigation condition, which is due to the reason that soil moisture is suitable for the growth of microorganisms under this irrigation patterns.