Based on the perspective of data factor value creation and using a sample of A-share listed firms from 2012 to 2022, this study investigates the existence, formation mechanisms， and heterogeneity of peer effect in corporate data factor investment. The results show that there is a peer effect in corporate data factor investment, and imitations based on learning and competition is a key motive for the formation of the peer effect in corporate data factor investment. The heterogeneity study finds that the strategic orientation of government data factor investment and the value synergy between technology factor and data factor can strengthen the peer effect. Further research finds that this peer effect is more obvious in non-eastern regions and non-SOEs. Extended analysis reveals that the peer effect in corporate data factor investment facilitates focal firms’ core technological innovation, enhances their total factor productivity, and fosters new quality productive forces.