The present invention relates to a petroleum-degrading bacterium in oily sludge. The degrading bacterium is preserved in CGMCC, General Microorganism Center of China Microbial Strain Preservation Management Committee, address: No. 3, Yard No. 1, Beichen West Road, Chaoyang District, Beijing, Institute of Chinese Academy of Sciences, Deposit number: CGMCC8647, classification number is Corynebacterium glutamicum. This application isolates oil-degrading bacteria (RS1) from oily sludge in Bohai Oilfield, and its preservation number is CGMCC8647. It has been proved by experiments that RS1 has a high degradation rate of saturated hydrocarbons, reaching 20.74%. The degradation rate of total petroleum hydrocarbons (TPH) was 39.69%. The optimal conditions for the bacteria to degrade petroleum were 37°C, salinity 0.5%-5%, and pH6-8.