Abstract: As the main carbon emission stage of oil & gas exploration and development, drilling and completion are important fields for achieving net zero emission. In this paper, the carbon emission footprint of the whole oil & gas industry chain and the trend of mitigating carbon emission of major oil service companies were summarized, and the development direction for carbon emission reduction during drilling and completion was analyzed. Specifically, it is necessary to upgrade the power system of drilling rigs and fracturing pump trucks, improve the automation level of equipment power management, strengthen the application of energy storage technology in drilling and completion, promote automatic drilling and completion and remote decision-making systems, and explore the coupling between drilling and completion and marine new energy,etc. Then, suggestions for carbon emission reduction during drilling and completion were proposed based on the carbon peak and carbon neutralization targets of China and oil & gas enterprises, as well as the technical level of drilling and completion. The suggestions include focusing on the carbon emission footprint of oil & gas exploration and development, strengthening the carbon emission management and promoting the low-carbon transformation during the whole drilling and completion process, improving the efficiency of drilling and completion, and exploring the utilization of marine new energy.As a result, these suggestions are of great significance to accelerate the carbon emission reduction of drilling and completion and meet China’s commitment to low-carbon transformation.