This book constitutes the proceedings of the 6th International Conference on Social Computing, Behavioral-Cultural Modeling and Prediction, SBP 2013, held in Washington, DC, USA in April 2013. The total of 57 contributions, which consists of papers and posters, included in this volume was carefully reviewed and selected from 137 submissions. This conference is strongly committed to multidisciplinarity, consistent with recent trends in computational social science and related fields. The topics covered are: behavioral science, health sciences, military science and information science. There are also many papers that provide methodological innovation as well as new domain-specific findings.