The purpose of this study was to revise the Osteoporosis Knowledge Test (OKT) and evaluate its reliability and validity. The original OKT, developed in the early 1990s, needed updating based on current research. A convenience sample of 105 adults completed the draft revised OKT. A subsample (n = 27) completed the questionnaire 2 weeks later to determine stability. The sample was recruited from diverse sites in western and northern Michigan over a year. The 32-item Revised OKT (2012) demonstrated internal consistency (total scale Kuder-Richardson-20 = .85, Nutrition subscale = .83, and Exercise subscale = .81). Test-retest analysis resulted in a Pearson correlation coefficient of .87. Validity was evaluated by content validity. Questions were examined for difficulty, effectiveness of distracters, and discrimination. In addition, measures of point-biserial, internal consistency and stability were determined. The Revised OKT (2012) is a comprehensive instrument reflecting current research and assesses osteoporosis knowledge of adults.