The purpose of this study was to identify the rates of absenteeism of nursing workers from a University Hospital due to diseases. Therefore, the author verified the number of absences due to health problems registered during 12 months, calculating the frequency rate as well as the percentage of wasted time. Data were collected and transcribed after consultation to reports organized by the human resources department of the institution studied. Results showed that the higher rate of absence occurred in the Pediatric Unit (If = 0.35) and the higher percentage of wasted time occurred in the Emergency Unit (Tp = 4.19). The author concluded that the rate of absenteeism due to disease was high among the workers, indicating the need of creating a database in order to optimize the registration of absences and their control as well as of stimulating the development of future research.