The development of artificial intelligence (AI) technology and the demand for general-subject teaching give birth to general-subject AI teacher-led courses. In this study, 79 fourth-grade pupils from two classes in a primary school in Guangzhou City are selected as the samples. The research methods of interview, classroom observation, and questionnaire survey are used to explore the effects of the AI general- subject teacher on pupils’ learning effectiveness based on the framework of anthropomorphic learning process theory. The results show that the AI general-subject teacher can significantly enhance pupils’ learning motivation (including intrinsic motivation and extrinsic motivation), increase pupils’ learning engagement (including behavioral engagement, cognitive engagement, and emotional engagement), and improve pupils’ learning outcomes (including knowledge and skills, process and method, emotional attitude and values). The findings confirm the important role of the AI general-subject teacher as the main instructor to promote pupils’ efficient learning and provide a significant reference for solving the shortage problem of excellent teachers and reducing the burden on teachers.