Objective : This study aims to investigate the characteristics of the types of disabilities of students in a specialelementary school class and a special-education school by applying a Korea Adaptive Behavior Scale (KABS)to examine their adaptive behaviors, and an School Function Assessment (SFA) to examine theirfunctional performance in school, and to show the correlation between the K-ABS and SFA. Methods : The teachers who had instructed the children for over 6 months filled in a questionnaire. In addition,the types of disabilities of the children were mental retardation, brain lesions, and developmental disorders. Astatistical analysis was conducted for the 67 questionnaires used in this study. Results : A high level of correlation was found between K-ABS and SFA in all disabilities of the children (Pearson, r=.93). There was a significant statistical correlation between the total K-ABS and SFA scores inall types of disability. Conclusion : The results of the present study showed a correlation between K-ABS and SFA. A follow- upstudy is needed to increase the validity through a more concrete disability classification.