Information about quality of life in patients with cancer in Arab populations in 21 countries is inadequate. The objective of this study was to assess the psychometric properties of the Arabic version of the European Organization for Research and Treatment of Cancer (EORTC) general quality of life questionnaire (QLQ-C30) and of the breast cancer-specific questionnaire (QLQ-BR23) in Arab breast cancer patients. The questionnaires were administered to 87 breast cancer patients 3 months after surgery. The mean age of patients was 48.6 years (SD: 9.9), 76% were married, all had staged disease (I, 9%; II, 46%; III, 44%; IV, 1%). The percentage of patients who underwent mastectomy and lumpectomy were 49% and 51%, respectively. Questionnaire reliability was assessed using Cronbach's alpha coefficient, in which the values were all >0.7, with the exception of cognitive function and pain in the QLQ-C30 (Cronbach's alpha 0.67 and 0.51, respectively) and breast symptoms in the QLQ-BR23 (Cronbach's alpha 0.50). The questionnaires' validity was confirmed using "known group comparisons," which showed that the QLQ-C30 discriminated between mastectomy and lumpectomy patients on the emotional and cognitive function scales (P < 0.001) and QLQ-BR23 discriminated as well on the function scales and for systemic side effects (P < 0.001). For the most part, QLQ-C30 and QLQ-BR23 distinguished clearly between subgroups of patients differing in their Hospital Anxiety and Depression Scale. In summary, the Arabic versions of the EORTC QLQ-C30 and QLQ-BR23 are reliable and valid tools for assessment of quality of life in Arab patients with cancer.