The purpose of this study was to develop and evaluate the validity and reliability of an instrument to measure nurse manager competencies regarding evidence-based practice (EBP). The Nurse Manager EBP Competency Scale consists of 16 items for respondents to indicate their perceived level of competency on a 0 to 3 Likert-type scale. Content validity was demonstrated through expert panel review and pilot testing. Principal axis factoring and Cronbach’s alpha evaluated construct validity and internal consistency reliability, respectively. Eighty-three nurse managers completed the scale. Exploratory factor analysis resulted in a 16-item scale with two subscales, EBP Knowledge (n = 6 items, α = .90) and EBP Activity (n = 10 items, α = .94). Cronbach’s alpha for the entire scale was .95. The Nurse Manager EBP Competency Scale is a brief measure of nurse manager EBP competency with evidence of validity and reliability. The scale can enhance our understanding in future studies regarding how nurse manager EBP competency affects implementation.