This book constitutes the refereed proceedings of the 5th International Workshop on Medical Imaging and Augmented Reality, MIAR 2010, held in Beijing, China, in September 2010. The 60 revised full papers presented were carefully reviewed and selected from 139 submissions. The papers are organized in topical sections on image segmentation, image registration, shape modeling and morphometry, image analysis, diffusion tensor image, computer assisted intervention, medical image computing, visualization and application, segmentation and classification, medical image understanding, image-guided surgery, and augmented reality.