Background and Objectives: Pulp stone (PS) is foci of calcification within the dental pulp whose etiology remains yet unknown. The prevalence of PS has been reported to very variable in other studies. The aim of this study was to determine the prevalence of PS in city of Rafsanjan.Methods: This descriptive cross-sectional study was carried out by periapical or bite-wing radiographs in 800 patients having referred to the department of oral and maxillofacial radiology of Rafsanjan dentistry school. Opaque masses were considered as PS in the coronal portion of the pulp. The data were analyzed by t-test and Chi-square statistical procedures.Results: The prevalence of PS was calculated to be 20% in 800 patients (21.7% men, 18.9% Women). There was no significant relationship between PS and gender. As age increased, the prevalence of PS increased (p<0.0001). There was a significant difference between the mean age of the patients with PS (31.7 9.62 years) comparable to patients without PS (28 8.75 years) (p<0.0001). The prevalence of PS was higher in first molar teeth.Conclusion: With regard to the results of this study, the prevalence of PS is rather high and increases with age. The high prevalence of PS and the probable common mechanism between PS and other diseases can be basis of designing more studies.