This book constitutes the refereed proceedings of the 18th International Conference on Formal Engineering Methods, ICFEM 2016, held in Tokyo, Japan, in November 2016. The 27 revised full papers presented together with three invited talks were carefully reviewed and selected from 64 submissions. The conference focuses in all areas related to formal engineering meth-ods, such as verification and validation, software engineering, formal specification and modeling, software security, and software reliability.