Caring is a behavior of giving holistic assistance to individuals. In fact, this important behavior still has not routinely performed in current nursing practice. Personality and sipirituality are important factors in forming one's caring behavior. Spirituality is a passion or impulse to perform noble action. The objective of this study was to explain the relationships of nurses' spirituality and caring behavior. This study was an observational research with cross sectional design. Study participants were ward nurse in three hospitals. The participants were recruited consecutively from untill the desired quota satisfied. Questionnaires on caring behavior and spirituality were used to collect primary data. Multivariate data analysis with Structural Equation Modeling-Partial Least Square (PLS-SEM) was used to analyze the data. The results showed no significant relationships between nurses' demographic characteristics (education, working experience, and wards type) and their spirituality or caring behavior. However, we found significant relationship of nurses' spirituality and caring behavior. In conclusion, nurses spirituality could affect caring behavior in positive ways and potentially improve nursing practice.