The present study investigated age-specific sex differences in the reciprocal action of personality factors of personality structure, using a three-factor personality model. The subjects were 280 healthy adolescents (15-17 years) and 337 elderly individuals who were not inpatients (65-98 years). Psychometric properties of BASIC-3 Personality Inventory indicated high homology between adolescents and elderly. A positive association between Sociability and Novelty-Seeking personality was found in all groups. In addition, the relationship between Novelty-Seeking and Neuroticism, and Sociability and Neuroticism personality traits displayed contrasting differences when the subjects were categorized by sex. Our findings suggest that there are age-specific sex differences in personality structure, and these results may contribute to psychological intervention for the elderly.