Petroleum wastewater, a complex byproduct of the oil industry, contains hazardous hydrocarbons, metals, and chemical additives, posing significant environmental risks. While conventional treatments partially mitigate these pollutants, bioremediation—a process using microorganisms, plants, or enzymes to break down contaminants—offers a sustainable alternative. This chapter explores microbial degradation, phytoremediation, and enzyme-based techniques, which leverage biological processes to transform pollutants into less harmful substances. The chapter discusses microbial pathways for hydrocarbon degradation, highlighting bacteria and fungi that thrive in toxic environments. Strategies like bioaugmentation, which introduces specialized microorganisms, and biostimulation, which enhances conditions for native microbes, are examined for their potential to improve efficiency. Phytoremediation is also explored, focusing on plant species that absorb or stabilize contaminants, making it a visually and ecologically appealing option. Advancements in enzyme-based bioremediation and genetic engineering of microorganisms are evaluated for future applications. Economic and environmental advantages of bioremediation over conventional methods are analyzed, supported by case studies demonstrating its effectiveness. Concluding with the challenges and future scope, this chapter provides insights into optimizing bioremediation as a viable, eco-friendly solution for petroleum wastewater treatment.