ObjectiveThis study aimed to investigate the expression patterns and relationship of microtubule-associated protein 1 light chain 3 (LC3B) and mammalian target of rapamycin (mTOR) in oral leukoplakia (OLK) in smokers and never-smokers. This work also analyzed the relationship between smoking and the carcinogenic potential of OLK.MethodsImmu-nohistochemistry was used to detect the expression of LC3B and mTOR in 120 patients with OLK. Clinical data from 120 smokers and never-smokers with OLK were analyzed. Subsequently, the relationships among LC3B and mTOR expression, clinical factors, and smoking were analyzed.ResultsSmoking and nonsmoking patients with OLK differed in terms of gender, age, lesion location, pathological typing, and carcinogenic situation. The positive rate of LC3B in never-smokers was higher than that in smokers. Whereas the positive rate of mTOR in smokers was higher than that in the corresponding never-smokers, and the differences were statistically significant (PPPConclusionThe effect of smoking habits on OLK may be linked to the expression of proteins that are directly associated with autophagy.