The refereed proceedings of the 6th International Workshop on Computational Processing of the Portuguese Language, PROPOR 2003, held in Faro, Portugal, in June 2003. The 24 revised full papers and 17 revised short papers presented were carefully reviewed and selected from 64 submissions. The papers are organized in topical sections on speech analysis and recognition; speech synthesis; pragmatics, discourse, semantics, syntax, and the lexicon; tools, resources, and applications; dialogue systems; summarization and information extraction; and evaluation.