BACKGROUND: This study aimed to compare the efficacy and safety of ciprofol-induced doses based on three indices: total body weight (TBW), ideal body weight (IBW), and lean body weight (LBW) in patients with obesity undergoing gastroscopy. METHODS: In a single-centre, prospective, randomised study conducted at an endoscopy centre, a total of 108 patients aged 18-65 years who underwent painless gastroscopy and had a body mass index (BMI) of 28-39.9 kg/m CONCLUSIONS: Induction doses of ciprofol based on TBW or IBW provided better anaesthesia than doses based on LBW for gastroscopy in patients with obesity. LBW-based induction doses of ciprofol improved cardiovascular stability and respiratory safety, whereas IBW-based induction doses of ciprofol reduced respiratory depression. TRIAL REGISTRATION: This study was registered in the Chinese Clinical Trial Registry (ChiCTR2300073539 first registration date 13/07/2023).