From the second year of life, children with typical development (TD) demonstrate the ability to form word-word relations. However, this ability has received little attention in children with Down syndrome (DS). We investigated their ability to establish associative relationships between words that tend to occur in the same context. Two groups of children (TD and DS) matched by sex and mental age (mean 3.80 years) participated in a preferential looking test. A priming task using an eye-tracking technique in ten trials introduced associatively related versus unrelated word pairs. Participants in both groups were asked to find a target image (e.g. hen) when they heard an associative prime that was related (e.g. egg) or unrelated (e.g. door), and the mean proportion of target looking was then calculated. Both groups showed an associative priming effect. The results suggest that people with DS possess a lexical organisation. This study represents a first step in understanding lexical networks, an important factor in language processing, in people with DS, which could be used to design interventions or educational strategies for language therapy.