With the deepening of oilfield development, the challenge of oilfield wastewater treatment has become increasingly prominent. This review systematically analyzes the sources and complex characteristics of oilfield wastewater, and comprehensively evaluates mainstream treatment technologies including physical, chemical, and biological methods. Through innovative integration and comparative analysis of technical advantages, disadvantages, and practical application cases, this study reveals that oil pollutants in oilfield wastewater rarely exist in a single phase, making integrated multi-process treatment (e.g., the combination of flocculation-sedimentation with scale inhibition, sterilization, and corrosion prevention) essential to meet discharge or reuse standards. Furthermore, the review proposes a technical roadmap for future development, emphasizing high-efficiency integrated processes, eco-friendly chemical agents, intelligent control systems, and water resource recycling. These findings provide a novel theoretical basis and practical guidance for advancing oilfield wastewater treatment towards sustainability and intelligence.