Objective: The purpose of this research was to study some biometric changes by comparing dermatoglyphic patterns of thumb between normal and congenital deaf girls in the population of Khorasan Razavi, Iran. Method: For this purpose, 79 healthy girls and 51 deaf girls (7 to 18 years old), all from Fars ethnical background, entered the study. The ink prints of their first phalange of the left and right thumbs (1RD, 1LD) were obtained and their dermatoglyphic patterns were compared in terms of quality and quantity. In analyzing the data, we used two soft wares: SPSS16 & MINITABA15. Results: The findings suggest asymmetry in deaf girls due to a significant difference in the ridge count of dermatoglyphic patterns between their right and left thumbs (P<0.05). Also, as for the frequency of the type of dermatoglyphic patterns in both deaf and normal groups, loop type was found to be the maximum and arch type, the minimum.Conclusion: Based on the findings of this study, 1RD and 1LD might be used as indicators of some biometric differences between normal and deaf girls; thus, useful for genetic studies.