Abstract Background Laryngeal mask airway(LMA) have been widely used in clinical practice. Irritation to the patient during the insertion of a laryngeal mask can cause hemodynamic fluctuations, which is particularly unsafe for geriatric patients. We used probit regression analysis to determine the median effective dose of sufentanil to inhibit the response to LMA insertion in geriatric patients. Methods A total of 90 patients were selected for the study using the following inclusion criteria: age ≥ 65 years old, ASA grade I–III, and scheduled to undergo intravenous general anesthesia with LMA insertion. Each patient received a dose of sufentanil for anesthesia induction in one of six levels: 0.05, 0.1, 0.15, 0.2, 0.25, or 0.3 μg kg−1. LMA insertion was scored with a 3-point, 6-category scale, with scores ≥ 16 indicating effective LMA insertion, and