This book constitutes the proceedings of the 6th International Workshop on Design, Modeling, and Evaluation of Cyber Physical Systems, CyPhy 2016, held in conjunction with ESWeek 2016, in Pittsburgh, PA, USA, in October 2016. The 9 papers presented in this volume were carefully reviewed and selected from 14 submissions. They broadly interpret, from a diverse set of disciplines, the modeling, simulation, and evaluation of cyber-physical systems with a particular focus on techniques and components to enable and support virtual prototyping and testing.