Total soil microbial activities have great impact to soil management for organic farming. This study was evaluated in the soil microbial community by fatty acid methyl ester (FAME) in a controlled horticultural field for strawberry organic farm. Experimental plots were prepared with a high level of soil electrical conductivity (EC) and a optimum level of soil EC. Soil microbial biomasses and communities of total bacteria, Gram-negative bacteria, Gram-positive bacteria, actinomycetes, fungi, and arbuscular mycorrhizal fungi in the high level of soil EC were significantly larger than those in the optimum level of soil EC. Lower ratios of cy17:0 to 16:$1{omega}7c$ and cy19:0 to 18:$1{omega}7c$ were found in the optimum level of soil EC than those in the high level of soil EC, indicating that microbial stress decreased.