The ionizing radiation used during endoscopic retrograde cholangiopancreatography (ERCP) can have harmful effects on patients and staff. The aim of the study was to determine the effect of radiation on nurses working in an ERCP unit. A descriptive, cross-sectional study was completed between June and August 2022 with the voluntary participation of 114 ERCP nurses. The data were collected using WhatsApp messenger through a Google Form. It was determined that, of the nurses, 68.4% received training on radiation safety, all of them took protective measures, 98.2% had knowledge about the effects of radiation, and 93.9% used dosimeters. Nurses stated that they mostly experienced fatigue (94.7%), loss of energy (68.4%), headache (39.3%), hair loss (35.1%), weakness (18%), leg and joint pain (15.1%), thyroid diseases (12.3%), skin discoloration (7.9%), and anemia (7.9%) as the possible effects of radiation during the period they worked in ERCP. The study found that 3.5% of the nurses were diagnosed with cancer while working in the endoscopic retrograde cholangiopancreatography unit. Additionally, ERCP nurses experienced the negative effects of radiation at different rates, but there was no significant relationship between demographic and health characteristics and experiencing the negative effects of radiation.