Bio remidiation possibility of soil contaminated by oil mud,and the optimization of the technological conditions for the bioremediation were studied using bio slurry reactor in pilot scale.A group of micro orgamism which are addicted to oil and rich in both amount and species in oil contaminated soil was discovered. Fusarium sp.was screeded for its high crude oil degradation rate.Oil mud with high concentration of crude oil was mixed with clean soil in the ratio of 1∶1,and 10% complex organic fertilizer and inorganic nutrients in proper proportion were added before treatment. Particularly,microbiological agent of indigenous superior strains for crude oil degradation was applied. Other operative conditions of the reactor included 25℃ for temperature and intermittent venting. After 75 days operation,the contents of total petroleum hydrocarbon (TPH) in oil mud was decreased from 43.39 to 0.72g·kg -1 .The degradation rate of TPH reached 98.3% under optimal conditions.