The quality of life (QOL) has been defined as ‘‘a person’s sense of well-being that stems from satisfaction or dissatisfaction with the areas of life that are important to him/her’’. It is generally accepted that pain intensity and duration have a negative impact on the QOL. One specific type of control is “self-efficacy”, or the belief that one has the ability to successfully engage in specific actions. The ability to adapt to pain may play an important role in maintaining the QOL. In this study, we investigated the role of self-efficacy, pain intensity, and pain duration in various domains of quality of life such as physical, psychological, social and environmental domains. In this study, 290 adult patients (146 men, 144 women) completed coping self-efficacy and the WHOQOL-BREF Questionnaire. Moreover, we illustrated numerical rating scale for pain intensity. The results were analyzed using SPSS version of 19.0 and means, descriptive correlation, and regression were calculated. Our data revealed that self-efficacy but not the pain duration could significantly anticipate the QOL and its four related domains (P<0.001). In addition, it is noticeable that the effect of self-efficacy on the prediction of QOL is much more obvious in the psychological domain. However, the pain intensity could predict all of the QOL domains (P< 0.001) except social and environmental ones. In conclusion, to predict the quality of life (QOL) in person suffering from chronic pain, self-efficacy and pain intensity are more important factors than the pain duration and demographic variables.