Autism spectrum disorder (ASD) is a neurodevelopmental condition characterised by language processing differences. These differences are thought to impact upon reading skill and individuals with ASD are often reported to have reduced reading comprehension and inferencing accuracy, in comparison to typically developing (TD) controls. This thesis examined on-line linguistic processing differences that might underpin atypical reading performance in ASD by monitoring the eye movements of TD and ASD adults as they read text that included lexical, syntactic, semantic, and discourse manipulations. Experiment 1 and Experiment 2 demonstrated that the efficiency of lexical and syntactic processing is similar between TD and ASD readers, as evidenced by comparable word frequency and garden path effects. In contrast, Experiment 3 demonstrated that there is a differential time-course in the processing of situational world knowledge during reading between TD and ASD readers. However, no difference in the efficiency with which TD and ASD readers form co-referential links was found in Experiment 4. In addition, for each experiment, readers with ASD were found to engage in increased rereading, in comparison to TD readers, which is speculated to reflect a ‘cautious’ reading strategy. Collectively, the findings from these experiments demonstrate that in general, the language processing system is very similar between TD and ASD readers. However, individuals with ASD have a specific processing atypicality that is associated with the processing of situational world knowledge. Given that processing of such information is often essential for inferences to be formed and for readers to achieve global text coherence, it is likely that this processing difference contributes to previous reports of comprehension and inferential atypicalities in ASD. Collectively, these findings provide a novel contribution to our understanding of how linguistic processing during reading occurs onlinein individuals with ASD.