Cleft palate is one of the most serious congenital anomalies in human that causes a sucking problem in newborn babies and morphologic deformity that usually leads to death in newborn mouse offspring due to an insufficient ability to suck milk. Therefore cleft palate had been researched with epidemiologic and molecular methods, and many etiologic factors were examined closely. Among of the research methods, biologic molecule researches have been more important method for cleft palate formation study. The $TGF-{eta}$ had an important role in the cell migration, epithelial-mesenchymal transdifferentiation, extracellular matrix synthesis and deposition. But there was a little research which was study about correlation cleft palate induced by beta-aminonitroproprionitrile(BAPN) with $TGF-{eta}$ expression. A purpose of this presented study was examed how $TGF-{eta}$ expression in cleft palate mice. At gestation days 13, BAPN-monofumarate salts($(C_3H_6N_2)_2$ ${cdot}$ $C_4H_4O_4$, Sigma Co.) was single oral administered to 4 pregnant rats according to 1g/kg body weight. And pregnant rats were sacrificed on day 20 post coitus(p.c.), The $TGF-{eta}$ expression patterns of cleft formed fetus mice was followed that; 1.Osteoblast, mesenchymal cell and epithelial cell of cleft mice were low expression compare to control mice. 2.There was no $TGF-{eta}$ difference expression pattern of osteocyte of cleft mice compare to control mice. 3. In western blot analysis, thickness of band of $TGF-{eta}$ in cleft mice was thin and dilute compare to control mice.