The purpose of this study was to understand nurses'' knowledge, performance, and degree of stress, and to analyze the correlation between nurses'' knowledge, performance, and stress on delirium care. Data was collected for 20 days from August 3rd to 22nd in 2012, and 222 surveys out of 250 were used for final analysis. For the study, a total of 50 following questions were used: 16 questions on the risk factors, 4 on the prognosis, 17 on the condition, and 13 on the intervention for delirium. A total of 23 questions were used for delirium nursing care performance, including 4 of delirium risk factor condition performance and 19 of nursing intervention. Twenty questions were used for delirium nursing stress. PASW Version 18.0 was used for data analysis. Percentage, average, standard deviation, t-test, ANOVA, and Pearson''s Correlation Coefficient were used for analysis The results of this study are as follows. 1. Nurses'' knowledge on delirium was scored 72.0 in average, in the questionnaire with 50 questions. For the subquestions on risk factors the average score was 76.0, knowledge on prognosis was 77.0, knowledge on condition was 76.0, and knowledge on intervention was 59.0 in average. 2. Delirium nursing care performance was scored 2.89 out of 4 in average, in the questionnaire with 23 questions. The subquestions on delirium nursing risk factors and condition performance were scored 2.94 in average, and the intervention performance was scored 2.88. 3. Delirium nursing stress was scored on 20 questionnaires with the perfect score of 100 point, and resulted in 59% in average. 4. The difference in nursing knowledge on delirium was found according to the general characteristics of subjects, total amount of clinical experience (F=3.120, p=.016), position at work (t=-2.536, p=.012), experience in caring the delirium patients (t=3.898, p=.000), and conflicts between medical staff and departments on matters related to delirium patients (t=4.001, p=.000). 5. The difference in delirium nursing performance was found according to the general characteristics of subjects, their age (F=4.185, p=.001), total amount of clinical experience (F=2.673, p=.003), transfer from room and hospital experience in orthopedics (F=3.242, p=.013), and whether there was a guideline for managing the patients with delirium (t=2.301, p=.022). 6. The difference in delirium nursing stress was found according to the general characteristics of subjects, and whether they had a religion or not (t=-2.414, p=0.017). 7. The relationship between nurses'' knowledge and performance on delirium care showed to have be positive (r=.212, p=0.001), the knowledge and stress showed a negative correlation (r=-.286, p=0.000), but there was no significant correlation between performance and stress of nursing for delirium patients. As a conclusion, education program and guideline development is greatly demanding increased level of nursing performance and knowledge on delirium for the nurses who work at orthopedic hospitals. The programs would need to manage the nurses'' stress.