The Sugarcane Ontology is a semantic knowledge model developed using the Web Ontology Language (OWL) to support structured representation and integration of data within sugarcane-based bioeconomies. The ontology captures key concepts, relationships, and processes across the sugarcane value chain, including production, processing, and bagasse valorisation pathways. It is designed to enable improved interoperability, data sharing, and decision support across agricultural, environmental, and industrial domains. By formalising knowledge in sugarcane-based bioeconomies, the ontology supports applications in sustainability assessment, resource optimisation, and bio-based systems analysis. The resource provides a foundation for developing intelligent systems, data-driven tools, and integrated decision-support frameworks. The ontology and associated code are openly available via GitHub to support reuse, extension, and collaborative development.