Background and aims: Recent research on problematic Facebook use has highlighted the need to develop a specific theory-driven measure to assess this potential behavioral addiction. The aim of the present study was to examine the factorial validity of the Problematic Facebook Use Scale (PFUS) adapted from Caplan's Generalized Problematic Internet Scale model. Methods: A total of 1,460 Italian adolescents and young adults (aged 14-29 years) participated in the study. Confirmatory factor analyses were performed in order to assess the factorial validity of the scale. Results: Results revealed that the factor structure of the PFUS provided a good fit to the data. Furthermore, results of the multiple group analyses supported the invariance of the model across age and gender groups. Discussion and conclusions: This study provides evidence supporting the factorial validity of the PFUS. This new scale provides a theory-driven tool to assess problematic use of Facebook among male and female adolescents and young adults.