The authors examined the decoding of the flouting of the Gricean relevance maxim among children with mental retardation compared to a mental age matched control group with average intellectual capacities, where the cause of mental retardation was perinatal hypoxia. They have investigated the decoding deficit by five short "question and answer" conversation vignettes, where the flouting of the relevance maxim was presented. They have found significant deficit in the mental retardation group in their capacity to decode properly the flouting of the Gricean relevance maxim. These data are the first that point at a pragmatic language use deficit in mental retardation caused by perinatal hypoxia.