Information development is a necessary means for China to achieve technology force and an effective path toward sustainable development. Regarding the "information benefiting people" policy led by the Chinese government as a quasi-experiment of information technology, this study builds an analysis framework for the impact of informatization on green total factor productivity (GTFP). Based on panel data at the Chinese city level from 2006 to 2019, this study further empirically evaluates the mechanism path, heterogeneity, and spatial spillover effects between informatization and GTFP by using a difference-in-difference (DID) model, a mediating model, and a spatial DID model. The results show that (1) the information benefiting people policy contributes considerably to greater GTFP levels in the pilot cities; (2) the policy also promotes the rapid growth of GTFP by fostering the advancement of education, the share of the number of ICT employees, and green technology innovation; (3) the information benefiting people policy raises GTFP in the eastern cities, small cities, and non-old industrial based cities; and (4) the policies lead to a large rise in local GTFP levels, but a decline in GTFP in surrounding cities. This paper offers valuable reference suggestions for the Chinese government to implement informatization-policies to support green development. • This paper investigates the effect of informatization on green total factor productivity (GTFP). • We use "information benefiting people" policy as a quasi-experiment. • The informatization promotes GTFP in China. • The education level, ICT employment share, and green technology innovation are suitable mediators. • The impact of informatization on GTFP is heterogeneous and spatially spillover. [ABSTRACT FROM AUTHOR]