Based on the panel data of Chinese listed and state-owned electronic and information companies, applying the theories of TMT faultlines and ownership structure, we probe the relationship between task-related TMT faultline and innovation performance, as well as the moderating role of the mixed-ownership structure in the relationship between TMT task-related faultline and innovation performance in the state-owned companies. The results of Fixed-Effects Negative Binomial Model analysis indicate that, first, the relationship between task-related TMT faultline and innovation performance is weakened when the level of balance between the equity proportion of big shareholders who represent state ownership and that of big shareholders who represent private ownership is high; while the relationship is not significant when the level of balance between the equity proportions of the above-mentioned two types of shareholders is low. Second, the positive effect of task-related TMT faultline on innovation performance is strengthened when the equity proportion of institutions investors increases. To strengthen the positive impact of task-related TMT faultline on innovation performance, enterprises with mixed-ownership structure should contingently arrange ownership structure to reduce the interest conflicts between the two types of shareholders, and try to improve knowledge integration within the TMT.