Objective To explore the effect of weight bias internalization on emotional eating in patients to undergo sleeve gastrectomy. Methods A total of 220 obese patients were conveniently selected for preoperative questionnaire survey, and the study instruments included the general sociodemographic inventory, the Weight Bias Internalization Scale （WBIS）, the Self-Esteem Scale （SES）, the Self-rating Depression Scale （SDS）, and the Three-Factor Eating Questionnaire-R21C （TFEQ-R21）. Results The emotional eating score averaged 14.13±4.90, and the weight bias internalization score averaged 52.31±11.51, with the two variables positively correlated （P＜0.01）.The results of structural equation modelling showed that, internalized weight bias directly affected self-esteem, depression or anxiety; it indirectly affected emotional eating behavior through the chain mediation of self-esteem and depressive emotions （all P＜0.05）. Conclusion Obese patients had higher rate of emotional eating and multiple mental health problems, through which, internalized weight bias indirectly affected emotional eating behavior.Medical staff should pay more attention to the psychological problems of patients, and actively formulate appropriate personalized psychological interventions for patients, in order to improve patients′ bad moods and correct their poor eating behavior.