Introduction: In the present study, perioperative outcomes of laparoscopy (LPS) were compared to open surgery (OS) for the treatment of large adnexal masses (AM).Material and methods: Retrospective observational cohort study. Data of consecutive patients who underwent ovarian cystectomy or salpingo-oophorectomy for large AM (diameter ≥10 cm) at a referral minimally invasive gynecologic center were analyzed. Propensity score match (PSM) analysis was used to minimize covariate imbalances between the two groups.Results: Overall 330 patients, 285 (86.4%) LPSs and 45 (13.6%) OSs were included. PSM showed LPS (vs. OS) to be associated with less intraoperative blood loss (mL: 131.1 ± 52.6 vs. 545.5 ± 101.2; p = .007), shorter operative time (min: 84.8 ± 77.9 vs. 123.7 ± 70.1; p < .001), but higher rate of spillage (54.5% vs. 12.1%; p < .001). Among the LPS group, a positive correlation between AM size and both conversion to open surgery and need for mini-laparotomy was found (p < .05).Conclusions: An accurate patient selection, a dedicated workup, and an appropriate counselling are mandatory before LPS for large AM. The increased risks of intraoperative spillage associated with the minimally invasive approach should be acknowledged.