Thirteen patients with gallbladder sludge, 14 patients with gallstones and 24 control cases with normal gallbladders were included in the study. Gallbladder function was represented as the filling fraction (FF) and the ejection fraction (EF) calculated using quantitative 99Tcm-DISIDA cholescintigraphy and compared in the groups. The results showed that (1) the patients with normal gallbladders had the highest FF and EF, (2) those with gallstones had the lowest FF, (3) the patients with gallbladder sludge had the lowest EF, and (4) the coefficient of variation (CV) of FF and EF of the normal controls were less than those for the patients with gallstones or sludge. There was only a statistically significant difference between the normal controls and the patients with gallstones for FF. However, no significant differences existed among the three groups for EF. In our preliminary results, we found that gallbladder sludge or stones may impair gallbladder function, especially FF, as evidenced by noninvasive and quantitative 99Tcm-DISIDA cholescintigraphy, and the higher CV value suggests that gallbladder function in patients with gallstones or sludge is more variable.