The purpose of this study is to develop service quality measurement model(DL-SQI model) which are able to measure objectively service quality of digital libraries in Korea and to measure user perceived service quality performance with DL-SQI model. This study also investigates the influence of service quality on customer satisfaction and customer loyalty. Before measurement, two principal rules and indicator formula were made to measure the service quality. Finally service quality of three digital libraries selected as samples was measured and analyzed in various points of view. It was developed a DL-SQI Consequences Model and testified it through path analysis using structural equation model.