The aim of this study was to develop a Cyberbullying Scale to measure cyberbullying behaviors of adolescents. For this aim, 24 items Cyberbullying Scale was administered to 515 (247 male, 268 female) students aged between 11 and 18 years-old from a public elementary school and different high schools in Istanbul. The content validity of scale was examined by three experts studying on this subject. Exploratory factor analysis was performed to test construct validity, and data revealed that scale was one factor. Reliability of scale was examined using Cronbach alpha and test-retest analyses. Results showed that Cyberbullying Scale could be considered as valid and reliable.