Based on the quasi-natural experiment of "reverse mixed ownership reform", this paper takes two types of strategic emerging industries, namely high-tech, energy conservation and environmental protection, and tests the influence of "reverse mixed ownership reform" on green innovation of private enterprises. The results show that "reverse mixed ownership reform" can promote green innovation of private enterprises in strategic emerging industries. The mechanism test found that "reverse mixed ownership reform" has the "dual effect" of developing specialization and easing financing constraints. Based on the comparative analysis of representative industries, it is found that the synergistic effect of "reverse mixed ownership reform" on green innovation of private enterprises in high-tech industries can be promoted through reasonable design of environmental regulations, and the complementary effect of "reverse mixed ownership reform" on green innovation of private enterprises in energy conservation and environmental protection industry can be promoted through reasonable strengthening and incentive of innovation subsidy policy. The study reveals the influence law of "reverse mixed ownership reform" to promote green innovation of private enterprises, and provides theoretical and policy inspiration for promoting the high-quality development of strategic emerging industries.