This study explored the Facebook addiction disorder (FAD) in Germany. Of the 520 participants, 6.2 percent reached the critical polythetic cutoff score and 2.5 percent reached the critical monothetic cutoff score. FAD was significantly positively related to Facebook use frequency, the personality trait narcissism, as well as depression and anxiety symptoms, but also to subjective happiness. Its association with resilience was significantly negative. Furthermore, Facebook use frequency partly mediated the positive relationship between narcissism and FAD. Current results provide a first overview of FAD in Germany. They demonstrate that FAD is not only the consequence of excessive Facebook use. The positive relationship between FAD and happiness contributes to the understanding of the mechanisms that are involved in the development and maintenance of FAD, and partly explains earlier inconsistencies. Practical applications for future studies and limitations of present results are discussed.