In order to study the influence of lateral depth of subsurface drip irrigation, aeration frequency and irrigation amount on soil enzyme activities and soil microbes of muskmelon grown in greenhouse, the experiment was carried out with orthogonal test design and using an air compressor to aerate the roots of muskmelon. Results showed that: ① Aeration had a significant impact on soil enzyme activities and soil microbial quantity. According to the influencing degree on quantity of rhizosphere soil bacteria and actinomycetes, these factors can be arranged as follow (descending): aeration frequencies, depths of subsurface drip irrigation and irrigation amount; for the catalase, urease and fungi amounts, the order of these factors (descending) was: depths of subsurface drip irrigation, aeration frequencies and irrigation amount. ② The optimal lateral depth of subsurface drip irrigation was 25 cm. ③ The greatest bacteria amounts and urease activities could be obtained through aerating once a day; the greatest fungi amounts and catalase activities could be obtained through aerating once every two days. ④ Catalase activity and actinomycetes quantity can reach the maximum when soil water content was attended to 80% of the field capacity; urease activity and bacteria quantity can reach the maximum when irrigation amount was attended to 90% of the field capacity.