13 cases of salivary glands and 30 of salivary gland tumors were studied by ABC method with 6 monoclonal antibodies to intermediate filaments and one to microfilament. The results showed that the distribution of intermediate filaments in salivary glands had their regularity. According to the reaction to the antibodies, these tumors could be divided into 3 groups and 3 subgroups. The findings also suggested that in the salivary gland tissue the epithelial cells which mainly contained the 54 Kd keratin and the epithelial cells which mainly contained 57/66 Kd keratin were the origin of the salivary gland tumors. The actin-positive myoepithelial cells might play a role in some tumor formation.