Landfarming and a microbial agent were used to treat dilsel-contaminated soil. The microbial agent was applied to the contaminated soil in a concentration of 5$ imes$102 cfu/soil(g) and the total amount of microbial agent, 210 l , was sprinkled on the soil four times for 24 days during 50 day-remediation period. The remediation goal, lower than 800mg/kg of TPH, was achieved from 5,707mg/kg of TPH within 50 days. The total number and activity of indigenous microorganisms were increased by 100 times after the microbial agent, Bioil-D, was applied to the contaminated soil.