Purpose: The purpose of this study is to identify the influencing factors on the nursing performance of dementia patients in long-term care hospital Nurses. Methods: Cross-sectional descriptive survey was used. Participants were 184 nurses who work at eight long-term care hospitals in D city and K region. The data were analyzed through descriptive statistic, t-test, one-way ANOVA, Pearson correlation coefficients, multiple regression analysis using IBM SPSS Statistics version 24.0. Results: Scores of dementia knowledge were 11.77, the correct answer rate was 73%, dementia attitude 4.66, nursing professionals 3.56, and dementia nursing performance was 3.07. As a result of stepwise multiple regression analysis, the factors influencing dementia nursing performance were dementia attitude (β=.40, p<.001), dementia education (β=.21, p=.001), and nursing professionalism (β=.18, p=. 005), and education level (β=.14, p=.016). Among them, dementia attitude appeared to have the most influencing factor effect on dementia nursing performance, and the explanatory power was 34.7% (F=25.30, p<.05). Conclusion: In order to improve the level of dementia care for long-term care hospital nurses, it is necessary to provide dementia education enhancing positive attitude toward dementia.