Twenty participants who were deaf and 20 chronological age-matched participants with typical hearing (TH) (mean age: 12 years) were asked to judge the correctness of written sentences with or without a grammatically incongruent word while their eye movements were registered. TH participants outperformed deaf participants in grammaticality judgment accuracy. For both groups, First Pass and Total Fixation Times of target words in correct trials were significantly longer in the incongruent condition than in the congruent one. However, whereas TH students showed longer First Pass in the target area than deaf students across congruity conditions, deaf students made more fixations than their TH controls. Syntactic skills, vocabulary, and word reading speeds (measured with additional tests) were significantly lower in deaf students but only syntactic skills were systematically associated to the time-course of congruity processing. These results suggest that syntactic skills could have a cascading effect in sentence processing for deaf readers.