This study aimed to analyze the adverse events reported in a public hospital within the scope of patient and employee safety, to develop studies aimed at learning from errors and to increase the awareness of healthcare professionals and to increase the quality of healthcare service provision. The research was designed as a descriptive, cross-sectional, and retrospective quantitative research design. Data were obtained from the Hospital Information Management System and written records with the data collection form created by the researcher. Data were obtained from the adverse events reported between 01.01.2022 and 30.12.2023. According to the findings of the research; A total of 3447 patient safety adverse event reports were made in 2022, and it was determined that 19 of them were falls, 8 were medication safety, 5 were transfusion safety, and 3415 were laboratory safety. A total of 4788 patient safety adverse event reports were made in 2023, and it was determined that 37 of them were falls, 20 were medication safety, 2 were transfusion safety, and 4729 were laboratory safety. In 2022, a total of 111 employee safety undesirable incidents were reported, of which 59 were sharp-edged injuries, 9 were blood and body fluid splashes, and 45 were legal incidents. In 2023, a total of 120 employee safety undesirable incidents were reported, of which 63 were sharp-edged injuries, 6 were blood and body fluid splashes, and 51 were legal incidents. When the 2022-2023 undesirable incident reports are compared, it is seen that the number of reports has increased over the years, which indicates that a reporting culture has been formed in the institution. As a result of the research; It was determined that the most reported undesirable incidents were laboratory safety and sharp-edged injuries.