Purpose: Using a longitudinal design, this study aimed to describe inferential comprehension abilities of neglected French-speaking preschool children from 42 to 66 months of age in comparison to non-neglected peers, to examine the association with receptive vocabulary, and to determine whether rates of change in inferential abilities over time was stable between the two group conditions. Method: An inferential comprehension task and the French version of the Peabody Picture Vocabulary Test--Fourth Edition were administered to a group of neglected children (n =37-40) and to a group of same-age non-neglected children (n =71-91) at 42, 54, and 66 months old, as part of the Early Longitudinal Language and Neglect study. Results: Results show that children exposed to neglect obtain significantly lower scores compared to their same-age peers on inferential comprehension and receptive vocabulary measures at all three time points (p < 0.001) with large to very large effect sizes and indicate moderate to strong correlations between the two variables. Children from the neglected group present difficulties in inferencing compared to same-age non-neglected peers, a disadvantage that remains stable over time. Conclusions: This study demonstrates the significant gap in inferential comprehension abilities between neglected and non-neglected preschool children. These results reiterate the importance of early detection of language comprehension difficulties in young children coming from vulnerable environments.