Abstract: Molecular biological methods were used to isolate and optimize strains from oilfield sludge and sewage, and to determine the potential of strains for oilfield sludge treatment. Meanwhile, different biological activators were screened and evaluated to improve the biodegradation environment of raw sludge. The biodegradation and remediation experiments were carried out by using the strains and bio-activators, investigating the change of oil removal rate of sludge. The results showed that the deoiling rate of oilfield sludge with less than 20 w% (dry weight) of oil content was 81.46% after 20-30 days of degradation, and after 1-2 growth cycles of phytoremediation, was less than 1.5 w% (dry weight) of oil content in sludge, which met the requirements of standard control indexes of oilfield industry.