Background: Researchers have acknowledged that examining ICT in relation to disciplinary learning outcomes could offer a promising, synergistic research path forward. A number of empirical studies have been done to determine the relationship between ICT-related variables and students' science achievement. However, the mechanism of the relationships remains unclear. Thus, in-depth investigations of the above relationships are needed. Purpose: This study examined the mechanism of how students' ICT availability, psychological need, satisfactions, and interest are associated with science achievement based on gender. Sample: This study used data of Program for International Student Assessment (PISA) 2015 B-J-S-G student questionnaire. B-S-J-G refers to the four PISA-participating China mainland provinces: Beijing, Shanghai, Jiangsu, and Guangdong, which includes 9841 students. Design and Methods: Underpinning by Self-Determination Theory (STD), a hypothesized model from ICT availability at home to science achievement that mediated by ICT psychological need, satisfactions, and interest were built. The model was tested by Structural Equation Modelling (SEM) along with the investigation of interrelationships among the factors in the model. Results: Findings from the path analysis indicated that (i) ICT availability at home has positive indirect relationships with science achievement and positive direct relationships with other ICT variables; (ii) ICT autonomy and interest have positive relationships with science achievement; (iii) ICT social-relatedness and competence have negative and no relationships with science achievement, respectively; and (iv) the relationships between ICT availability at home and science achievement varied across genders. Conclusion: A valid model of relationships from ICT availability to students' science achievement that mediated by ICT psychological needs and interest was established. Based on the model, recommendations of developing students' ICT interest and autonomy, especially for female students, were provided. Further research could offer keen insights into the areas of ICT investment and practice.