Stage ⅠA3 non-small cell lung cancer (NSCLC) represents a high-risk subgroup within early-stage lung cancer, characterized by significant prognostic heterogeneity and ongoing controversies in treatment strategies. This review systematically summarizes the prognostic features and driving factors of stage ⅠA3 NSCLC, with a focus on high-risk pathological markers such as spread through air spaces (STAS), lymphovascular invasion (LVI), and tumor-stroma ratio (TSR), and their roles in prognostic stratification. We further analyze their clinical implications in surgical extent selection and adjuvant therapy decision-making. By integrating advanced technologies such as radiomics and artificial intelligence, we discuss recent advances in preoperative prediction and postoperative personalized adjuvant therapy. We propose a precision treatment strategy based on multimodal risk models, aiming to provide evidence-based guidance for clinical practice and facilitate the transition from anatomic staging to biology-driven individualized management for stage IA3 NSCLC.