Preterm birth is associated with an increased risk of executive function (EF) deficits, yet the underlying neural mechanisms remain unclear. We combine diffusion MRI, resting-state functional MRI, and graph theory analyses to examine how structural (SC) and functional connectivity (FC) at term-equivalent age (TEA) influence EF outcomes at 3 years corrected age in children born at or below 32 weeks' gestation. Here we show shorter average path length (a measure of efficient structural communication) in the insula is linked to better EF performance, implying that more direct structural pathways in this region facilitate critical cognitive processes. Additionally, higher betweenness centrality (a node-level metric of information flow) in parietal and superior temporal regions is associated with improved EF, reflecting these areas' prominent integrative roles in the whole-brain functional network. Importantly, our multimodal analyses reveal that regional structural efficiency helps shape functional organization, indicating a specific interplay between white-matter architecture and emergent functional hubs at TEA. These findings extend current knowledge by demonstrating how earlier disruptions in SC can alter subsequent FC patterns that support EF. By focusing on precise node-level metrics rather than broad within-network effects, our results clarify the contribution that SC has in guiding functional relationships essential for EF.