Objective：To evaluate the effect of laparoscopic sleeve gastrectomy（LSG）on the psychological and quality of life of young obese patients with acanthosis nigricans（AN）and explore the mechanism. Methods：Clinical data of 52 young AN patients who underwent LSG surgery at Shanghai Tenth People's Hospital from January 2020 to December 2022 were retrospectively collected，and 50 healthy individuals were selected as the control group（CON）. The Beck self-rating depression scale -Ⅱ was used to evaluate the psychological status，and the Chinese version of SF-36 was used to evaluate the quality of life of the subjects. The anthropometries parameters，glucose metabolic indicators，lipid metabolism indicators，and C-reactive protein（CRP）levels of AN patients were evaluated and calculated before and 12 months after surgery，and compared before and after surgery. Correlation analysis was performed between depression and related metabolic indicators. Results：The scores of each dimension of quality of life assessment in the AN group before surgery were significantly lower than those in the CON group（P < 0.05），and the incidence of depression（63.5%） was significantly higher than that in the CON group（P < 0.001），with a significantly higher severity of depression than the CON group （P < 0.001）. The levels of fasting insulin，insulin resistance，blood lipids and CRP of the AN group before surgery were significantly higher than those of the CON group（P < 0.05）. Twelve months after surgery，as the weight of AN patients decreased，blood lipids and CRP levels significantly decreased，and their hyperinsulinemia and insulin resistance significantly improved. Meanwhile，the mental health score in the SF-36 scale of AN patients significantly increased，and the depression score and severity also significantly improved. Depression scores in patients were positively correlated with body mass index，insulin resistance，and CRP. Conclusion： Depression in AN patients is closely related to increased insulin resistance and inflammatory factors. LSG effectively improves depression and quality of life in AN patients by reducing weight，improving insulin resistance，and inflammation.