Context: Aims: This study was aimed to assess the prevalence of C-shaped root canals in maxillary molars by analyzing cone-beam computed tomography (CBCT) in Iranian population. Settings and Design: Material and Methods: In this descriptive cross-sectional study, 450 extracted maxillary molars were examined by CBCT (NewTom FP QR-DVT 9000 Verona, Italy) radiography. The images were analyzed using NewToms’ NNT software and examined by an oral and maxillofacial radiologist and an endodontist to determine the absence or presence as well as classification of C-shaped canals. Statistical analysis was done by SPSS version 21.0. Results: Of the 450 teeth studies, 24 (5.33%) had C-shaped canals and 426 (94.66%) had normal anatomy. Moreover, the highest type, observed among the study population, was type B1 (Based on Martin classification). Conclusions: The result of this investigation demonstrated that 5.3% of the Iranian population teeth have C-shaped morphology.