tongue epithelial cytochemistry indexes in 33 cases of white tongue coatings,35 cases of yellow tongue coatings and 26 cases of normal tongue coatings were detected with microspectrophotometry, and compared according to the syndrome differentiations. The results showed that in white tongue coating group.all of the indexes but G-6-PDH were lower than those in normal group,and LDH, MDH and ACPwere significantly different (P