The clinical value of salivary gland scintigraphy (RI-sialography) was studied in 11 cases with definite Sjögren's syndrome. Time-activity curves which were obtained from computer-assisted analysis of RI-sialography were classified into 4 types (N:normal type, M:median type, F:flat type, S:sloped type), and the efficacy of scintigraphy in evaluating salivary gland function and the relationship between time-activity curves and other diagnostic methods are discussed. Flattened time-activity curves such as F- or S-type were more often seen in submandibular glands than in parotid glands. Flattened curves were not seen in the early stage of the inflammatory process; conversely, when we found a flattened curve, it suggested a wide destruction of the salivary gland tissues. Correlation between time-activity curve and sialography showed 90.9%, and correlation between time-activity curve and histopathological change in the minor salivary gland of the lower lip also showed 90.9%.