Objective：To clarify the developmental status of porcine fetal kidney at different stages，and to study the expression of signaling molecules related to the development of porcine fetal kidney. Methods：The kidney tissues of porcine fetuses at different stages（fetuses on post-implantation days 21.5，27.5，35.0，45.0，75.0 and 110.0）were collected. The histological structure of pig fetal kidneys was observed by HE staining. The mRNA and protein expression levels of factors related to renal development signaling molecules（Pax2，Pax8，Six2，Six1，Sall1 and Bmp4）were detected by quantitative real-time PCR（qPCR）and Western blot，respectively. The expression and localization of Pax2 at different stages of fetal kidney were detected by immunohistochemistry. Results：The metanephros of fetal pig initiated its development starting by the 27.5th day. The early renal corpuscles appeared on the 35th day，and the renal tubules began to develop. On the 45th day，the immature glomeruli in the cortex region and the proximal matured renal corpuscles in the medulla region could be detected. The number of nephrons on the 75th day increased significantly，and kidney pyramid，renal papillae and renal pelvis were observed at this stage. On the 110th day，kidney was basically mature，the cortex and medulla could be distinguished clearly，and new nephrons kept to be produced. The mRNA and protein expression levels of Pax2，Pax8，Six2，Six1，Sall1 and Bmp4 on 75 d were higher than that on 35 d. Pax2 was widely expressed in ureteric bud，metanephric mesenchyme，cap mesenchyme，renal vesicles，comma-shaped bodies，S-shaped bodies and renal tubule，and is continuously expressed during the development of the metanephros. Conclusion：The development of metanephros of fetal pig starts the 27.5th day and basically reaches maturation on the 110th day. The signaling molecules such as Pax2，Pax8，Six2，Six1，Sall1 and Bmp4 were expressed along different stages during the kidney development，and Pax2 may be a key regulator of porcine fetal kidney development.