The use of autochtonious bacterial strains is a valuable bioremediation strategy for cleaning the environment from hydrocarbon pollutants. The isolation, selection and identification of hydrocarbon-degrading bacteria is therefore crucial for obtaining the most promising strains for decontaminate a specific site. In this study, two different media, a minimal medium supplemented with petroleum and with oil refinery sludge as sole carbon source, were used for the isolation of native hydrocarbon-degrading bacterial strains from crude oil contaminated soils and oil refinery sludges which allowed isolation of fifty-eight strains. The evalution of diversity of twenty-two bacterials isolates reveled a dominance of the phylum Proteobacteria (20/22 strains), with a unique class of Alphaproteobacteria, the two remaining strains belong to the phylum Actinobacteria. Partial 16S rRNA gene sequencing performed on isolates showed high level of identity with known sequences. Strains were affiliated to Sinorhizobium, Promicromonospora, Novosphingobium, Georgenia, Ancylobacter, Roseomonas, Hansschlegelia and Tistrella genera. Research for the genes that encoding for degradation enzymes in isolated genera genome data deposited in Genbank reveled the presence of degradation gene in three species Sinorhizobium meliloti, Novosphingobium panipatenseand Tistrella mobilis.