Abstract: A new round of scientific and technological revolution and industrial transformation is in the ascendant. The Internet, big data and artificial intelligence are closely integrated with traditional industries, and new type industrialization is accelerating. Major projects are one of the core links of new type industrialization construction, and are related to national construction, national revitalization, and even the future of mankind. While creating well-being for mankind, they also breed a series of ethical risks that cannot be ignored. Under the background of the digital economy era, major projects fall into a series of ethical dilemmas due to the coexistence of subjectivity and objectivity of major project risks, the difficulty of tracing the collective responsibility of major projects, the constant changes in the ethical concepts of the engineering community, and the application of artificial intelligence in major projects. Therefore, we should strengthen the technical risk prevention and cognition of major projects, take into account the "soft constraint" of self-discipline and "hard constraint" of heteronomy, and explore the "golden mean" of major projects governance and ethical governance.