The magnitude of the brucellosis problem in the Gaza Strip and the exposure to risk factors among cases were investigated. The incidence of brucellosis in 1996 was 8/100 000. The age-specific incidence rate was approximately equal in all age groups, with a mean age of infection of 20 years. Cases were reported from all districts, with a particularly high incidence in the Mid-zone district and Gaza City, and most cases had onset of illness in spring and summer. The main reported risk factor was consumption of milk and milk products, especially home-made cheese [70.4%], and 22.2% of cases were among animal breeders. The proportion of chronic and relapsing cases was very high [17%]