DNA synthesis is one of the most basic, widely-used tools in life science as well as a key enabling technology in synthetic biology. The rapid development of industrial biotechnology promoted by synthetic biology is creating an insatiable demand for large-scale DNA synthesis from more convenient, economical and safe sources. Industrial DNA synthesis platforms have remarkable advantages in terms of throughput, cost and speed. The research and development processes of industrial biotechnology benefit from these advantages, achieving a higher efficiency and lower cost. However, challenges in DNA manufacturing process remain, such as the use of large amounts of organic reagents, waste of resources and so on. With the continuous and rapid increase of DNA synthesis scale, the hazard of toxic chemicals, cost burden and environmental burden are becoming prominent. Based on our practical work on DNA synthesis, we discuss the demand and strategies for large-scale DNA synthesis in industrial biotechnology as well as the issues and potential solutions for sustainable development.