This study was done to evaluate the quality of clinical nursing care using the variables of structure, process, and outcome and to analyze the relationship between the variables. This study also explored which variables are validating indicators to evaluate the quality of nursing care. The results analyzed by multiple regression showed that, generally structural variables did not contribute to the variance in outcome scores, but process variables of nursing care contributed significantly to the outcome variable of patient satisfaction. A combination of structure and process variables explained outcome variables more than structural variables alone. Also, patient satisfaction and hospital preference were significantly related to each other. Therefore, if nursing quality evaluation relies solely upon on structural variables such as number of available nurses and workload, it would be inaccurate because process variables of nursing care are strongly related to outcome variables and the two categories of structure and process variables helped to strengthen the relationships. Thus, it is important to focus on variables of structure, process, ant outcome together in evaluating nursing care quality.