Abstract: In the context of “carbon peaking and carbon neutrality” and the transformation of energy consumption structures in oil and gas well sites, the integrated development and intelligent regulation of fossil fuels alongside new energy sources such as wind, solar, and geothermal energy have emerged as a new model for the future energy system. The construction of multi-energy complementary energy systems in oil and gas production well sites contributes to cost reduction, efficiency enhancement, and low-carbon transformation. From the general to the specific, the connotation and key technological progress of multi-energy complementary energy systems in general scenarios were discussed. Then, the technical framework and practical paths of the optimization technology of multi-energy complementary energy systems in oil and gas production well sites were investigated, and the dynamic energy consumption characteristics of core production systems such as mechanical production, water injection, and gathering and transportation were thoroughly analyzed. Based on the specific characteristics of oil and gas production scenarios, the key technological advancements in multi-energy complementary energy systems in oil and gas production well sites were systematically summarized from four dimensions: source-load prediction, capacity optimization, coordinated scheduling, and energy efficiency evaluation. Additionally, the typical application models of multi-energy complementary optimization technologies in the low-carbon transformation of Chinese and international oil companies were reviewed. Finally, the challenges and future research directions for the application of multi-energy complementary energy system optimization technologies in oil and gas production well sites were identified, with the aim of providing a systematic theoretical reference and practical guidance for the green transformation of the oil and gas industry.