Labial salivary gland biopsy (LSG-B) along with Schirmer test and kerato-conjunctival staining with fluorescein dye was performed in 196 patients with suspected Sjogren's syndrome (SS). Of the 196 patients, 117 were found to have 2 or more lymphocytic focus scores (LFS/4mm2) on their LSG-B specimens. 92 of them having keratoconjunctivitis sicca (KCS) as well met the diagnostic criteria of SS. Among the cases (25) without KCS, 16 with another CTD were diagnosed as secondary SS. 9 cases were classified as probable primary SS in this study because they had clinical manifestations of SS. Of the 11 cases with KCS only, 6 with another CTD were diagnosed as secondary SS; 5 befitted primary SS for abnormal findings on sialography. We also found that lymphocytic infiltration in LSG-B was much more severe in primary SS than in secondary SS; this could be attributed to the use of immunotherapy for the accompanying CTD in secondary SS. There was good association in our study between the severity of lymphocytic infiltration and systemic involvement.