It‘s important to treat diabetes by awareness of complication, because if left without awareness of its complications diabetes can become severe and lead to serious complications requiring emergency care, such as diabetic coma. Therefore we designed a cross–sectional survey in order to assess the awareness of diabetic population about the complications and its prevention. The study included all adult population who are registered at one primary health care center in AL–Hasa. The total 72 patients were interviewed based on a structured questionnaire. The overall awareness is very poor. Furthermore the results showed no significant (P>0.05) difference among different age groups and education status, while socio–economic groups and gender have differences (P<0.05). Thus it is concluded that population requires a large–scale health education program in order to prevent complications in diabetic patients.