Real time RT-PCR was applied to study the developmental patterns of leptin and leptin receptor gene mRNA expression at the ages of 1, 27, 90, 150 and 180 days after born (DAB) in subcutaneous fat and hypothalamus of Lantang and Landrace pigs. The results showed that: (1) in subcutaneous fat, Lantang had the highest leptin mRNA level at 180 DAB. Leptin mRNA at all ages in lantang was higher than that in landrace, except at 1 DAB. Leptin mRNA was significantly higher in Lantang pig than that in landrace pig at 180 DAB. Leptin mRNA had no significant difference among landrace pigs at all ages. (2) In hypothalamus, leptin receptor mRNA was highest at 180 DAB for both the two breeds, and it had significantly higher than that at other ages in lantang, and at 1 and 27 d in landrace. Two breeds at 1 d had apparent differed.(3) Lantang pigs at all ages had higher serum leptin level than landrace. Two breeds at 150 d were the highest compared with other ages. Lantang pigs at 150 day had significantly higher than at ages of 27 and 180 day. No significant changes were seen in all ages in landrace.