The study offers a retrospective analysis of data collected from reading comprehension activities of two groups of English foreign language (EFL) learners, one with and one without dyslexia. The aim of the investigation was to verify whether vocabulary depth corresponds to greater accuracy in answering factual and inferential questions in the two groups. The hypothesis was that depth would be associated with better comprehension even in dyslexic readers’ performance, which was generally poorer than that of the control group. In fact, this was only confirmed for high-range focus words, that is, words that were more deeply known to the participants according to an adapted Word Associates Test. Variable outcomes were observed for mid- and low-range words. A qualitative analysis of the unexpected results was carried out which led to the identification of several factors hindering text comprehension by dyslexic readers. These include a difficulty in selecting the relevant sense of focus words in contexts in which competing elements coexist and a negative interaction between lexical and pragmatic-inferential processing.