Objective:To compare the clinical efficacy and cost of robot-assisted laparoscopic adrenalectomy with da Vinci Xi and Si surgical system in the treatment of adrenal tumors.Methods:The clinical data of 99 patients performing robotic-assisted laparoscopic adrenalectomy in our hospital between June 2019 and December 2020 were retrospective analyzed. Among them, 57 cases were Si system robot assisted laparoscopic adrenalectomy (group Si), 35 male, 22 female; age (45.6±14.0)years; BMI(21.0±1.2); 6 with diabetes, 10 hypertension, 14 with abdominal surgery; 28 left, 29 right; 9 ASA score ≥3; tumor diameter (3.9±1.2)cm. There were 42 cases of Xi system robot-assisted laparoscopic adrenalectomy (group Xi), 21 male, 21 female; age(44.8±14.5)years; BMI(21.4±1.8); 2 with diabetes, 12 hypertension, 11 with abdominal surgery; 15 left, 27 right; 7 with ASA score ≥3; tumor diameter (3.7±1.1) cm. Sex, age, BMI, comorbidities, history of abdominal surgery, lateral division, ASA score, and tumor diameter were not significantly different between the two groups ( P>0.05). Operation method: except for the different docking procedures, the same surgical procedures were roughly performed in the two groups. The docking method of the Si group was the doctor holding the attractor as the guide. The operating room nurse introduced the robot cart under the guidance of the attractor, and then completed the docking.Group Xi docking adoptd the own laser positioning system of the robot system, without manual positioning and guidance; the mechanical arm of the Xi system was also more flexible. Complications were graded according to the Clavien-Dindo grading system. Comparing the treatment effect, safety, and cost of the two groups were compared. Results:The anesthesia times in the Si and Xi groups were (140.0±24.3) min and (125.6±26.4) min ( P=0.006), respectively. The surgical times in the Si and Xi groups were (109.0±18.8) min and (98.8±20.7) min (P=0.013), respectively. The docking times between the Si and Xi groups were (7.8±1.4) min and (5.0±0.9) min ( P<0.001), respectively. The estimated intraoperative blood loss in the Si and Xi groups was (121.5±70.8) ml and (124.7±68.9) ml ( P=0.824), respectively. The postoperative indwelling times of the drainage tube in the Si and Xi groups were (3.4±1.2) d and (3.4±1.3) d ( P=0.892), respectively. Postoperative bed times in the Si and Xi groups were (2.3±1.0) d and (2.5±1.2) d ( P=0.419), respectively. Postoperative hospitalization times in the Si and Xi groups were (6.4±1.5) d and (6.2±1.5) d ( P=0.484), respectively. Post Clavien ≥ grade 3 complications were four and two in groups Si and Xi, respectively ( P=0.642). The total cost during hospitalization in the Si and Xi groups was (51 975.2±7 320.8) Yuan and (56 830.9±8 392.5) Yuan, respectively ( P=0.003). The surgery and consumables costs for the Si and Xi groups were (23 785.3±4 063.1) Yuan and (28 021.2±6 066.8) Yuan ( P<0.001), respectively. Conclusions:Compared with the Si system, the Xi system robot-assisted laparoscopic adrenalectomy can provide similar perioperative results and safety, and shorten the time of anesthesia and surgery, but the total cost of hospitalization is increased.