This study was performed for evaluation of GB wall thickness according to interval change and transaminase level in acute hepatitis. We studied 43 cases with acute hepatitis who were developed their symptoms within 1 week before admission. Ultrasonography and serum transaminase level(SGOT, SGPT) were checked after 12 hour fasting and follow-up serum transaminase and ultrasonography were done by regularly 1 week interval. Nineteen cases of normal adults were studied for control group by ultrasonography as same way after confirming absence of gallbladder disease on static B-scan. The results are summarized as follows; 1) In control group, the thickness of gallbladder wall was 2.74+-0.57 mm. 2) In acute hepatitis group, the thickness of gallbladder wall at 1st week from onset of disease was4.9+-81.03 mm, at 2nd week 3.78+-1.07 mm and at 3rd week 2.78+-0.80 mm. There were statistical significance between control and acute hepatitis at 1st and 2nd week but it returned nearly normal at 3rd week. 3) There were no correlations between serum transaminase level and thickness of gallbladder wall at 1st, 2nd and 3rd week after onset 4) There was no significant difference in the thickness of gallbladder wall between groups with high serum transaminase (above 500 U/L) and low serum transaminase (below 500 U/L)