Oily wastewater treatment in the petroleum industry may generally be classified as process wastewater pretreatment, primary treatment, secondary treatment, and tertiary treatment or polishing. In secondary treatment, dissolved oil and other organic pollutants may be consumed biologically by microorganisms. Biological treatment of complex chemicals in the petroleum industry wastewaters is specially challenging due to the inhibition and/or toxicity of these compounds when they serve as microbial substrates. Processes such as sequencing batch reactor (SBR) technology which promote the mineralization of the petroleum industry wastewaters containing toxic compounds seem to be promising. In this study, principles of SBR, modifications in SBR technology, effective parameters on SBR process, and recent developments in the application of SBR technology for the petroleum industry wastewater treatment have been reviewed.