Abstract: Objective To investigate expressions and role of glial cell line-derived neurotrophic factor (GDNF)，GDNF family receptor alpha l (GFRα1) and RET in the development of mice kidney. Methods Immunohistochemistry and Western blot were used to detect the expressions of GDNF, GFRα1 and RET in E 12 d, E 14 d, E 16 d, E 18 d, N 1 d, N 7 d, N 14 d, N 21 d and N 40 d mice kidneys. Results The results showed that GDNF, GFRα1and RET were expressed in the early stage of renal development. The weak expressions of GDNF, GFRα1and RET were detected in the ureter bud, and the weak expressions of GDNF and GFRα1 were detected in metanephrogenic tissue. During the development process of renal corpuscles, GDNF and GFRα1 were expressed obviously in vesicle bodies, comma-shaped bodies and S-shaped bodies, while they were expressed weakly in capillary loop stage and immature renal corpuscles. With the mature of renal corpuscles, expressions of GDNF and GFRα1 disappeared. During the development process of uriniferous tubule, GDNF and GFRα1 were expressed in renal tubules (proximal tubule and distal tubule); GDNF, GFRα1 and RET were expressed in collecting ducts. In mature kidney, GDNF and GFRα1 were expressed in renal tubules and collecting ducts, RET was expressed in collecting ducts. Western blot results showed that, with the development of kidney, the expressions of GDNF, GFRα1 and RET increased at frst, and reached to the peak at E 18 d (GDNF) and N 1 d (GFRα1 and RET). Then, expressions of GDNF, GFRα1 and RET in kidney decreased along with neonatal age. Conclusion GDNF/GFRα1/RET signaling pathway plays an important role in different development stages of kidney and in maintaining the function of mature kidney.