The extensive application of AI technology to second language teaching has become an irreversible trend, adding new vitality to teaching practices. At the same time, Sociocultural Theory (SCT), as a significant theoretical paradigm in contemporary second language acquisition research, has also gained increasing attention. The full integration of SCT with AI in second language teaching is of significant theoretical value and application potential. Based on research related to SCT, AI, and second language teaching from core domestic and international journals, this study explores the rationale for SCT to guide AI-empowered second language teaching. With the three core concepts of SCT (internalization, mediation, and the Zone of Proximal Development), it outlines the implementation pathways for AI-empowered teaching and demonstrates their feasibility. Furthermore, it analyzes three teaching application forms (“AI-driven interactive teaching”, “multimodal content-assisted teaching” and “real-time dynamic assessment and feedback”) and showcases the practical application of AI technology within the SCT framework. Finally, it highlights the potential challenges in current practices, providing references for subsequent research and teaching reform.