Syntax and prediction are fundamental elements supporting the processing of language and music. Implicitly learned syntactic rules and principles allow perceivers to form expectations (or predictions) about the syntactic combination of individual elements, resulting in facilitated processing of upcoming expected events. The current chapter discusses syntax (in the broad sense of structured, system-based combinations of events) and prediction in language and music, including an outline of the formal similarities and differences in syntax between the two domains. It presents behavioural and neural evidence showing the role of syntax in prediction, for both typical and pathological populations as well as connections with rhythm processing. Methodological considerations for future research investigating syntax and prediction in language and music are also discussed, as well as perspectives for rehabilitation and training, notably based on predictive processing informed by syntactic and rhythmic principles in both domains.