Objectives. To assess the incidence of priapism in the general population. Methods. We conducted a population-based retrospective cohort study within a general practitioners research database. Our study population comprised all male patients with permanent registration status with a general practitioner. All patients with an International Classification for Primary Care code for penile problems (Y01, Y04, Y08) were identified. In addition, a free text search on priapism and painful erection was conducted. The computerized medical records from all potential patients were reviewed, and we requested additional information from the general practitioner if priapism was suspected. Results. The total study cohort comprised 145,071 men, with a total follow-up of 341,133 person-years. Five patients developed a first occurrence of priapism during the follow-up period, corresponding to an overall incidence rate of 1.5 per 100,000 person-years (95% confidence interval 0.2 to 2.8). The incidence rate in men 40 years old and older was 2.9 per 100,000 person-years (95% confidence interval 0.1 to 5.7). No cause of priapism was apparent in 2 patients, 2 cases occurred after intracavernous injection of vasodilators, and 1 patient experienced priapism because of sickle cell disease. Conclusions. The incidence of priapism is low but seems higher than was previously assumed. Copyright