Background : There have been many studies and efforts about quality management in health services, but there were not founded quality assessment on social services. This study was designed for understood level of quality on social service, identified for correlation factors of quality assessment on social services in general and teaching hospitals in Korea. Methods : The subjects of this survey were 80 leaders of social service units. The survey data from each subjects were measured to evaluate level of quality that service provider perceived of sample hospitals. Social worker's attitude of quality assurance activities, perception of quality assurance system in that hospitals were measured. Under the method of one-way ANOVA, t-test and correlation, associated factors of quality assessment in social work service was analyzed. Results : The major findings were as following ; First, the level of quality perceived showed less score, especially the lowest was the score of quality of outcome. Second, social worker's attitude of quality assurance activities showed high score, but quality assurance system of hospitals showed less score. Third, the level of quality assurance system of hospitals, social worker's attitudes of quality assurance activities. Conclusion : The quality of social work service correlated positive hospitals's quality assurance system, social worker's attitudes of quality assurance activities. Therefore, to assure the proper level of quality, qualified for hospitals system of quality assurance, and needed to a educational program for enhanced social workers's attitudes in quality assurance activities.