The authors studied to evaluate the difference of the diagnostic performance between reading from digital image on the video CRT of PACS (Picture Archiving and Communication System) and from analogue image of conventional film mode. We compared interpretative accuracy of above two reading modes by having two observers read a series of liver scintigrams. Images were read once from film and a second time from video CRT of elementary PACS. The concordance rate of interpretation of the two modes was in the range from 61.0% to 93.2%. The diagnostic accuracies of digital image reading and analogue image reading were 72.9% and 74.6% respectively in one observer, and 72.9% and 76.3% in another one. No significant difference in interpretative accuracy could be found between two modes of reading.