Objective To explore the risk factors of early postoperative hypoxemia in obese patients after laparoscopic sleeve gastrectomy (LSG). Methods A total of 271 obese patients, aged 18‒50 years old, body mass index (BMI)≥35 kg/m2, men or women, at American Society of Anesthesiologists (ASA) grade Ⅰ‒Ⅲ, who underwent LSG under general anesthesia from January 2017 to December 2021 were selected and their clinical data were retrospectively analyzed. According to the presence of hypoxemia 30 min after entry into postanesthesia care unit (PACU), they were divided into two groups: a hypoxemia group [partial pressure of oxygen/fraction of inspiration O2 (PaO2/FiO2)≤300 mmHg (1 mmHg=0.133 kPa), n=93] and a non‑hypoxemia group (PaO2/FiO2>300 mmHg, n=178). Their general information, preoperative smoking history and basic medical history, preoperative examination results, operation and anesthesia‑related factors were analyzed by univariate analysis. Factors with statistical differences between the two groups were included into multivariate logistic regression analysis to evaluate the risk factors of early hypoxemia after LSG in obese patients. Results The incidence of early postoperative hypoxemia was 34.7%. Compared with the non‑hypoxemia group, the hypoxemia group showed increases in the proportion of male patients, body weight, BMI, history of obstructive sleep apnea hypopnea syndrome (OSAHS), and the dosage of sufentanil (all P<0.05), and extended operation time (P<0.05), as well as decreases in preoperative forced expiratory volume in one second (FEV1) and PaO2 (all P<0.05). Multivariate logistic regression analysis showed that BMI [odds ratio (OR) 1.340 (95% confidence interval (95%CI) 1.171, 1.535), P<0.001], history of OSAHS [OR 2.800 (95%CI 1.423, 5.511), P=0.003] and the duration of operation [OR 1.041(95%CI 1.017, 1.066), P=0.001] were the independent risk factors for early postoperative hypoxemia in obese patients after LSG. Conclusion BMI, OSAHS history and operation time are the independent risk factors for early postoperative hypoxemia in obese patients after LSG.