This study was aimed to explain academic procrastination based on locus of control and religious beliefs. A sample of 447 Shiraz University students (225 females and 222 males) who were selected via purposive sampling procedure participated in the research. Academic Procrastination Scale, Internal Locus of Control Scale, and Scale of Religious Orientation with Emphasis on Islam were completed by participants. Generally, results showed that academic procrastination, as a total score, can be negatively predicted by internal locus of control and ethic component in religious orientation. It was revealed that ethic component in religious orientation and internal locus of control are significant negative predictors for procrastination in preparing homework (assignments) and procrastination in preparing term papers، as two components of academic procrastination. Procrastination in preparing for exams, as another component of academic procrastination, can be predicted by none of independent variables. Comparison for gender differences showed that male students scored significantly higher than females in general academic procrastination and procrastination in preparing assignments. Also, it was revealed that students who were studying in religion-relevant disciplines, scored significantly lower than students who were studying in religion-irrelevant disciplines in academic procrastination scale and its subscales. In the final section of article, findings are discussed in the light of previous literature and suggestions for further research in this area are set forth.