The problem addressed by this study were to explore the effect of hardiness on psychosocial adjustment of persons with a colostomy and to identify factors which influence that psychosocial adjustment. The purpose was to suggest a theoretical base for the planning of supportive nursing interventions to increase the level of adjustment. Among members of the Korea Ostomy Association, 34 subjects who had undergone colostomy from March, 1990 to March, 1991 were selected as the sample. Data were collected from April 8 to May 8, 1991 using a mailed questionnaire. The instruments used for this study were the Health -Related Hardiness Scale(Pollock, 1984) and the Psychosocial Adjustment to illness Scale (Derogatis, 1975). ANOVA, Pearson correlation coefficient and Stepswise Multiple Regression were used for data analysis. The results of the study are summarized as follows. 1. Hardiness was significantly related to psychosocial adjustment(p＝0.009). That is, the higher the hardiness, the higher the level of psychosocial adjustment. 2. Among the demographic variables, only economic level was significantly related to the level of psychosocial adjustment. (p＝0.005). 3. The important factors influencing the level of psychosocial adjustment of persons with a colostomy were economic level, commitment, challenge (subconcepts of hardiness). Therefore, in order to increase the level of the psychosocial adjustment, it might be helpful to provide them with hardiness training to strengthen their commitment and their challenge.