Abstract. This paper describes our approach to the Question Answering - Word Sense Disambiguation task. This task consists in carrying out Question Answering over a disambiguated document collection. In our approach, disambiguated documents are used to improve the accuracy of the retrieval phase. In order to do this, we added a WordNet-expanded index to the document collection. The expanded index contains synonyms, hypernyms and holonyms of the words already in the documents. Question words are searched for in both the expanded WordNet index and the default index. The obtained results show that the system that exploited disambiguation obtained better precision than the non-WSD one.