Abstract: To research the signal mechanism between epidermal growth factor （EGF） and tongue-coating formation，the mice tongue mucosa cell growth with EGF-R expression was observed after droping EGF to mice mouth cavity.HE、EGF-R immuno-histochemistry （SABC） and by data handles system （CMIAS-98A） to proceed the image analysis were used. The results showed that EGF promotes the thickening of tongue mucosa in experiment mice，and the base layer cells and the EGF-R expression of tongue mucosa were increased.The EGF might influence the tongue-coating formation by the signal conduct mechanism of EGF-R.

Key words: Epidermal growth factor, Tongue-coating, Immunohistochemistry, Image analysis, Signal conduct mechanism