Risk perception of acquiring vaccine preventable diseases and the immune status of 187 health care workers (HCW) from a high-complexity university hospital in São Paulo, Brazil, were assessed. The vaccine preventable diseases more cited as at risk for acquisition were hepatitis B (94.1%), influenza (92.5%), meningococcal disease (90.3%), tuberculosis (85.0%), and varicella (72.7%). Previous disease or vaccination reported by HCW were hepatitis B (82.4%), tetanus (87.7%), diphtheria (81.8%), measles (86.6%), mumps (85.6%), rubella (85.0%), varicella (82.9%), and influenza (35.8%). One third of HCW reported previous percutaneous or mucosal occupational accidents, and 83.6% had notified the event to the Hospital Infection Control Committee. Despite good risk perception of acquiring vaccine preventable diseases, only 35.8% of individuals were fully immunized. Efforts should be made to increase influenza vaccination coverage among all professionals and to reduce the number of nonreported accidents, especially among physicians.