The present study aimed at developing a scale measuring attitudes towards old people reliably and effectively. A large scale questionnaire survey was conducted targeting all age groups in Taiwan. There were a total of 991 usable questionnaires (368 adolescents, 230 college students, 393 adults). Results revealed that internal consistency reliability was high for the overall “Old People Scale” (OPS) (α = .91), and generally acceptable for its four subscales (Appearance and physical characteristics, Psychological and cognitive characteristics, Interpersonal relations and social participation, and work and economic safety). The OPS also showed good convergent validity and criterion validity. We also found that males compared to females, had more positive attitudes pertaining to Psychological and cognitive characteristics. Finally, those who had more positive attitudes towards old people were more willing to interact with them in various social situations.