Objectives: To analyze perforation rate in sterile gloves used by surgeons in the operating theatre of the Department of Endocrinological and General Surgery of Medical University of Lodz. Material and Methods: Randomized and controlled trial. This study analyses the incidents of tears in sterile surgical gloves used by surgeons during operations on 3 types of thyroid diseases according to the 10th revision of International Statistical Classification of Diseases and Related Health Problems (ICD-10) codes. Nine hundred seventy-two pairs (sets) of gloves were collected from 321 surgical procedures. All gloves were tested immediately following surgery using the water leak test (EN455-1) to detect leakage. Results: Glove perforation was detected in 89 of 972 glove sets (9.2%). Statistically relevant more often glove tears occurred in operator than the 1st assistant (p < 0.001). The sites of perforation were localized mostly on the middle finger of the non-dominant hand (22.5%), and the non-dominant ring finger (17.9%). Conclusions: This study has proved that the role performed by the surgeon during the procedure (operator, 1st assistant) has significant influence on the risk of glove perforations. Nearly 90% of glove perforations are unnoticed during surgery.