The purpose of this study was to evaluate the impact of tailored individualized nursing care services on the self-efficacy perceptions and healthy lifestyle behaviors of older adults living in a nursing home in Turkey. This outcomes evaluation research used a quasi-experimental study design in which outcomes evaluations were repeated within time intervals in a single group. The study sample included 30 older adults. Nursing diagnoses and interventions were identified using the Omaha System. The impact of implemented nursing care services was evaluated using the Self-Efficacy Scale and Healthy Life-Style Behaviours Scale II. A total of 3,024 nursing interventions were performed, and self-efficacy perceptions and healthy lifestyle behaviors of older nursing home residents were significantly increased in a positive manner (p < 0.05). The results suggest that nurses should assess self-efficacy perceptions and healthy lifestyle behaviors of older adults and that nursing care services directed at health promotion of older adults should be maintained.