This book constitutes the thoroughly refereed post-conference proceedings of the 11th International Conference on Unconventional Computation, UC 2012, held in Orléans, France, during September 3-7, 2012. The 28 revised full papers presented were carefully selected from numerous submissions. Conference papers are organized in 4 technical sessions, covering topics of hypercomputation, chaos and dynamical systems based computing, granular, fuzzy and rough computing, mechanical computing, cellular, evolutionary, molecular, neural, and quantum computing, membrane computing, amorphous computing, swarm intelligence; artificial immune systems, physics of computation, chemical computation, evolving hardware, the computational nature of self-assembly, developmental processes, bacterial communication, and brain processes