Interest in biodegradation of petroleum derived pollutants by thermophilic bacteria has been steadily increasing in recent decades. In this work, a newly isolated thermophilic bacterial strain was isolated from a deep petroleum reservoir and identified as Anoxybacillus sp. WJ-4 based on an analysis of its physiological characteristics, 16S rRNA sequencing, GC content and cellular fatty acids. It is the first report that strain WJ-4 can degrade a wide range of hydrocarbons (C8–C22) at 67 °C. The production of an oligosaccharide–lipid–peptide bioemulsifier was detected. It exhibited an excellent emulsification activity with various oil phases (EI₂₄ > 60%), and the ability to increase cell surface lipophilicity during degradation, but has no significant impact on surface tension, with a reduction from 72.22 mN m⁻¹ to 52.45 mN m⁻¹. Four alkane monooxygenase genes showed a high phylogenetic relationship (>95%) with alkB genes from Geobacillus. These results indicate that this newly isolated bacterial strain and its bioemulsifier have great potential for environmental remediation and petroleum recovery under thermophilic conditions.