Ten primary health care clinics in the Gaza Strip were randomly selected from the five regions that form the Gaza Strip (Southern region, Gaza City, Middle region, Khan-Younis and Rafah). The objective of the present study was to investigate the prevalence of mental health problems among patients attending primary health care clinics in the Gaza Strip. Six hundred and sixty-one randomly selected primary health care patients from the five regions were surveyed using the HSCL-25. Seventy-three per cent of patients visiting primary care clinics in the Gaza Strip had psychiatric symptoms consistent with psychiatric disorders. The prevalence of mental health problems among females was higher (76.8%) than males (67%). Previously married and single patients reported more distressing symptoms than married people. The results also revealed that the prevalence of mental health problems was higher among patients living in refugee camps. Civic status was not associated with mental health problems.