This book constitutes the refereed proceedings of the Second International Workshop on Simulation and Synthesis in Medical Imaging, held in conjunction with MICCAI 2017, in Québec City, Canada, in September 2017. The 11 revised full papers presented were carefully reviewed and selected from 14 submissions. The contributions span the following broad categories: cross modality (PET/MR, PET/CT, CT/MR, etc.) image synthesis, simulation and synthesis from large-scale image databases, automated techniques for quality assessment images, and several applications of image synthesis and simulation in medical imaging such as image interpolation and segmentation, image reconstruction, cell imaging, and blood flow.