Objectives: The aims of the present study were to determine anterior and total tooth-width ratios in a representative Iranian sample in Tabriz city and compare them with the Bolton standards. Study design: A total of 54 Iranian schoolchildren (12-14 years old) in Tabriz were examined. Alginate impressions were taken for subjects and poured by the dental stone. The mesiodistal widths of the teeth were measured using a digital caliper. The overall and anterior Bolton's intermaxillary tooth size ratios for each model pair was calculated. Results: There were no significant differences (p > 0.05) between the right and left sides of the dental arch and a symmetry in size exists. There were no significant differences between genders for all teeth measured except for the maxillary central incisors, maxillary canines and mandibular canines. Anterior and overall Bolton ratios for males were 77.72±0.25 and 92.44±0.19 and for females were 78.48±0.30 and 92.45±0.23 percent, respectively. There were no statistically significant differences between males and females for the anterior and overall ratios. The anterior and overall Bolton ratios among Tabrizian schoolchildren were 78.10±0.28 and 92.24±0.21 percent, respectively. There was no statistically significant difference between these ratios and those were found in the Bolton study. Conclusion: No significant differences between the mesiodistal sizes of contralateral teeth were observed and a symmetry in size exists. There were no significant differences in the mesiodistal sizes of similar teeth between males and females except for the maxillary central incisors, maxillary canines and mandibular canines. Significant differences in Bolton ratio between males and females, and examined population (student from Tabriz, Iran) and the Bolton's weren't observed either. © Medicina Oral S. L.