Using a panel of Chinese A-share listed firms from 2009 to 2022, this study investigates whether data assetization promotes corporate long-term investment. The results show that data assetization significantly increases long-term investment, with a stronger effect on R&D than on capital expenditures. Mechanism analyses suggest that this association is consistent with improved risk perception, reduced information asymmetry, and enhanced financial resource allocation efficiency. Further analyses show that the effect is more pronounced in more competitive industries, among firms with stronger corporate governance, and among growth-stage firms. These findings provide empirical evidence on the role of data assetization in firms’ long-term investment decisions and offer implications for advancing the integration of the digital economy with the real economy.