Currently, countries all over the world are deeply promoting the digital transformation of education. There is a lack of empirical research on the relationship between education digitization and education effectiveness. This study aims to explore the contribution of education digitization to education effectiveness through empirical research. This study first constructs a theoretical model of the impact of education digitization on education effectiveness based on relevant theories. The original dataset of the 2022 PISA mainly consists of mathematics, reading, and science assessment scores obtained through machine tests or paper assessments and the results of the generic student questionnaire covering multiple measurement dimensions such as ICT familiarity. This study conducted an empirical analysis based on 53,908 data selected from 2022 PISA data. The results show that digitization does not have a significant direct positive effect on educational effectiveness but indirectly affects educational effectiveness by influencing teachers' teaching behavior and students' learning behavior. It is found that teachers' teaching behavior and students' learning behavior respectively play an intermediary role in the influence of digitization on educational effectiveness, but at the same time, teachers' teaching behavior and students' learning behavior also play a chain intermediary role in the influence of digitization on educational effectiveness. This study also shows that grade and gender are important moderating variables of the influence of digitization on educational effectiveness. Based on the research results above, relevant measures can be taken to promote the development of digital transformation of education.