In order to explore the differences of muscle growth and development between Wuzhishan pigs and Landrace pigs at the later stage of growth, in this study, an isobaric tag for relative and absolute quantification(iTRAQ) based proteome were used to analyze total protein of the longissimus dorsi muscle tissues of at the age of 6 months and 8 months of the two studied pig breeds. Combined with bioinformatics methods to sort out the differential proteins KEGG pathway enrichment analysis of differential proteins were performed to characterize the difference. The results showed that a total of 1713 proteins were identified in the four collected group samples. Comparing the 6-month-old and 8-month-old Wuzhishan pigs with those of Landrace pigs, 460 and 337 different proteins were found, respectively. The comparison of the two growth stages in the breed showed that there were 421 differential proteins in Wuzhishan pigs and 275 differential proteins in Landrace pigs, and the results were the same as one of intervarietal comparison, which was the number of up-regulated differential proteins was more than the number of differential down-regulated proteins. Based on the KEGG pathway enrichment analysis, 34 and 33 items with significant difference(P<0.05) between the two growth stages of 6-month-old and 8-month-old of Wuzhishan pigs and Landrace pigs were found, respectively. While within the breed, the terms enriched were 24 and 14, respectively. The PI3K/AKT signaling pathway, which plays an important role in regulating skeletal muscle differentiation, and the PPAR signaling pathway that affect fat deposition, were found in the breeds; among breeds, the glycolysis/gluconeogenesis signaling pathway related to the development of muscle fiber types was also found. There were 10 and 9 genes co-expressed in PPAR and PI3K/AKT signaling pathways in the two groups within the breed, respectively. While 10, 13 and 9 genes co-expressed in glycolysis/gluconeogenesis, PI3K/AKT and PPAR signaling pathways between the two comparied groups, respectively. After analyzing the genes commonly expressed in these signaling pathways, some key genes linked to the muscle growth and fat metabolism were screened.