Abstract: The effect of the anaerobic-aerobic fermentation and the function of addition of fowl manure as nutrients on the stabilization and harmlessness of oily sludge as well as composted sludge recycling were studied during the investigation of the possibility of thermophilic aerobic fermentation of oily sludge. It is shown by the results that the dewatered oily sludge mixed with additional fowl manure nutrients can be effectively fermented and stabilized by thermophilic aerobic method with an efficiency of oil removal about 60% or more. However, the oil removal by anaerobic- aerobic fermentation is not significantly better than by direct aerobic fermentation; the composted sludge can partly replace the nutrients and bulking agent during oily sludge aerobic fermentation. It is suggested that the optimized parameters of oily sludge aerobic fermentation are: air supplying rate from 0.025 m3/ (m3?h) to 0.05 m3/ (m3?h), the volumetric ratio of oily sludge to fowl manure nutrients of 3:1.