The loach is one of the most important fish species in aquaculture in China. The study of peroxisome proliferator-activated receptors (PPARs) will be essential for the determination of the functional role of the PPARα and PPARγ in loach fish. We used immunohistochemistry for PPARα and PPARγ at some stages of development beginning from the age of 1 month till the age of 15 months. Our result indicated that the expression of  PPARα and PPARγ was found in; columnar cells lining intestinal folds, hepatocytes, blood sinusoids in the liver, pancreatic islets, pancreatic acini, the whole spleen and epithelial cells lining renal tubules of the kidney. The expression pattern of both PPARα and PPARγ was low at the age of one month, then reach its highest level at the age of 2 months. Then it declines at the age of 5 months. Then it re-increase at the age of 7 months and became low in older ages. The expression of PPARα was higher in comparison with PPARγ.