Based on the perspective of the cohort effect theory, we construct a director-supervisor tenure network and use a sample of A-share listed companies in Shanghai and Shenzhen stock exchanges from 2010 to 2021 to investigate whether the technological innovation behavior of focal firms is influenced by the technological innovation of peer firms, i.e., whether there is a cohort effect of corporate technological innovation in the director-supervisor tenure network, and further analyze the transmission mechanism. The results of the study show that, firstly, the technological innovation of the peer enterprises has a significant promotion effect on the technological innovation of the focal enterprises. Second, peer firm technological innovation promotes focal firm innovation by stimulating focal firm innovation motivation and optimizing focal firm innovation process. Third, due to the substitution relationship between internal information channels based on network association and external information channels, the peer effect in director and supervisor tenure networks plays a greater role when the external information environment is poor. This paper deepens and enriches the research on the peer effect of corporate innovation and its mechanism based on a new network perspective, which provides new policy ideas for corporate technological innovation in the context of the increasing importance of innovation and increasingly close corporate linkages.