ABSTRACT Objective Adolescence is an important time period in smoking experimentation and initiation. This study examined heterogeneity in key beliefs about smoking intention among Chinese adolescents. Methods Survey data came from 951 students (18 and 19 years) in two high schools in Kunming, Yunnan Province, China. The survey questions assessed smoking beliefs and perceptions based on the Theory of Planned Behavior. Regression and latent class analysis were utilized to identify key beliefs (i.e., beliefs that are most influential in smoking intention) and their heterogeneity. Results Emotion-related beliefs were reported by both genders, highlighting the role of anxiety and stress in smoking intention. Female and male adolescents had different sets of key beliefs. There were distinct subgroups of beliefs in the sample (two among female adolescents, and three among male adolescents) characterized by disparate patterns of behavioral beliefs, normative beliefs, and control beliefs and smoking status. Conclusions Considerable heterogeneity in belief profiles, which differs based on gender and smoking status, furnishes a more complete understanding of smoking intention among Chinese adolescents. Gender-specific anti-smoking interventions can be targeted to the beliefs of specific subgroups of adolescents. Stress management for students could also be a useful tool to prevent smoking uptake.