Medical students’ subjective well-being is closely associated with academic stress, psychological flexibility, and neuroticism; however, the heteroge

Background/Objectives: Short video addiction (SVA) has become a matter of public health concern, impacting the well-being of college students. However, previous studies have largely treated SVA as a homogeneous phenomenon, overlooking the potential heterogeneity in addictive behaviors among individuals and their underlying mechanisms. This study aims to identify distinct SVA subtypes and explore the mediating role of inattention (IA) in the relationship between these subtypes and negative emotions. Methods: The present study recruited a sample of college students through a multicentre online survey conducted from January to August 2025. Latent profile analysis identified distinct SVA categories among college students, and further examination of the mediating role of IA between SVA and negative emotions (anxiety, depression) was undertaken. Results: Latent profile analysis stratified SVA into three cohorts: “Healthy short video use” (8.9%), “Short video dependence” (55.8%), and “Short video addiction” (35.3%). The subtypes differed in levels of IA, anxiety, and depression (p < 0.05), with IA functioning as the link between SVA and negative emotions. It is noteworthy that IA demonstrated a complete mediating effect in the anxiety model, thereby indicating that the adverse impact of SVA on mental health is predominantly mediated by impaired attention function. Conclusions: This study deepens the understanding of students’ SVA from a heterogeneity perspective and provides empirical evidence for exploring the potential cognitive mechanisms through which SVA influences mental health. It is suggested that targeting attention function may hold great value in alleviating SVA-related psychological issues.