Using graduate social work students' data ("n" = 481) in the Hartford Partnership Program for Aging Education (HPPAE) in the United States, the study examined psychometric properties of the Knowledge of Aging for Social Work Quiz (KASW), a revision of the Facts on Aging Quiz, to evaluate biopsychosocial knowledge relevant to social work. We examined the intercorrelations of the KASW with the academic and practice experience in aging and score differences by the specialization and school year, and estimated the internal consistencies as reliability. Results showed the convergent validity of the KASW, indicating the items measured theoretically related areas of content with students' skills and experiences in aging. The internal consistencies, nevertheless, remained relatively low, representing the items that failed to measure the expected constructs of biopsychosocial domains. The KASW will be further refined to more sensitively identify students' knowledge deficiencies by selecting an optimal panel of items in biopsychosocial content areas and by providing information relevant to the pedagogical agenda and guidance in field education.