A survey was carried out on a sample of 973 nurses from hospitals in the Valencian Region. The objective was to study work absenteeism due to health reasons depending on socio-demographic factors, work organization and self perception of health status. Information was collected by means of a self-administered questionnaire. Duration and frequency of absenteeism was analysed over the previous twelve months. A 34.4% of female nurses and 35.4% of male nurses reported at least one episode, with an average length of 21 and 26 days respectively. There is a relation between absenteeism and self-perception of health status. We did not find man/woman differences with regards to absenteeism.