This book constitutes the refereed proceedings of the 15th International Conference of the Pacific Association for Computational Linguistics, PACLING 2017, held in Yangon, Myanmar, in August 2017. The 28 revised full papers presented were carefully reviewed and selected from 50 submissions. The papers are organized in topical sections on semantics and semantic analysis; statistical machine translation; corpora and corpus-based language processing; syntax and syntactic analysis; document classification; information extraction and text mining; text summarization; text and message understanding; automatic speech recognition; spoken language and dialogue; speech pathology; speech analysis.