Objective To investigate if there are differences in the skin tissue structure between BALB/c mutant mice with curly hair and normal BALB/c mice. Methods 10-d,21-d,42-d and 63-d old groups of BALB/c mutant curly mice and normal BALB/c mice were used in this study, 10 mice in each group. The gross appearance of the mice were observed.Hair follicle and skin structure were examined and compared by histopathology. Results Clothing hair of the BALB/c mutant curly mice became bent at 10 day after birth,and could be distinguished from normal mice of the same age.Histological observation showed that the number of hair follicles and hair roots of BALB/c mutant curly mice was significantly less than that of normal mice, and the sparse coat and hair curling characteristics were obviously kept to 21 d, 42 d and 63 d of age.Histopathological examination revealed that the number of hair follicles in the mice in the four age groups of BALB/c mutant curly mice was also significantly less than that of normal mice.At 63 days of age, bending curly hair growing in hair follicles were visible in the BALB/c mutant curly mice. Conclusion Hair follicles and the skin tissue structure in the BALB/c mutant curly mice and normal mice showed distinct differences.These results demonstrate that the skin structure of mutant mice is also changed, which can provide a theoretical reference for future research on the mouse curly hair mutant gene and model application.