Promoting the digital transformation of enterprises is an inevitable requirement for achieving high-quality economic development. The command-and-control environmental regulation represented by the pilot policy of low-carbon cities plays an important role in the construction of "digital China". In view of this, this paper took the pilot policy of low-carbon cities as the entry point, and based on the data of China"s A-share listed companies from 2007 to 2021, adopted the staggered differential model to empirically-test the impact of the implementation of command-and-control environmental regulation policies on the digital transformation of enterprises. It is found that the implementation of low-carbon city pilot policies can effectively force the digital transformation of enterprises, and this conclusion is still valid after considering the heterogeneity of treatment effects and a series of robustness tests. Mechanism analysis shows that reducing carbon emission level, stimulating enterprises" green innovation and easing financing constraints are the main ways for low-carbon city pilot policies to improve the digitalization level of enterprises. At the same time, the overseas background of directors has a positive moderating effect on the process of promoting the digital transformation of enterprises by the low-carbon city pilot policy. Further analysis shows that the policy effect will show heterogeneity due to the differences of enterprise ownership type, industry type and industry type. In addition, the implementation of this policy can also bring corporate dividends and social welfare. The research conclusions have important implications for how the government can use macro-control methods to force digital transformation of enterprises, so as to achieve green economic transformation and development.