The nursing process, composed of diagnosis, intervention and outcome, is practical and scientific approach. In addition, many studies on the nursing process have been performed. However, the nursing process has not applied to clinical fields. Therefore, we developed a nursing information system that supports nurses nursing diagnosis and intervention management. This system provides expected nursing diagnoses and interventions for subjective patients automatically so that nurses can make more accurate diagnoses and perform more adequate interventions. For that purpose, we have analyzed the relations of medical diagnoses and standardized nursing classifications and developed the outputs into a database system. In this study, we performed clinical tests for the system and verify the usefulness of the system with case database accumulated through the tests. We expect the system can be used in many hospitals efficiently after some upgrade based on the results of this study is completed.