Streptomycessp. S501, which was isolated from the sediment of Yalujiang Estuary in China, was the first marineStreptomycesspecies discovered to act as an excellent petroleum degrader. We analyzed the effect of pH, temperature, and concentration of NH(4)NO(3)on the petroleum degradation of strain S501, and the optimum biodegradation rate reached 63.02% under the condition of 2 g/L NH(4)NO(3)addition at 30 degrees C and pH 8. The complete genome sequence ofStreptomycessp. S501 was determined by using the PacBio RSII platform, which contains a linear chromosome with 7,173,651 bp and a linear plasmid with 288,181 bp, with GC contents of 71.19% and 67.57%, respectively. The genome sequence suggests thatStreptomycessp. S501 has the ability to degrade several hazardous pollutants, as well as the ability to biosynthesize diverse secondary metabolites and enzymes. There are fifty annotated genes involved in oil component degradation, and there are three genes without known annotation information inStreptomycessp. S501, which have high homology with genes encoding P450 family enzymes and should be novel genes involved in alkane degradation. This study provides useful genetic information for investigating the molecular mechanisms of marineStreptomyces, with biodegradation and application potential.