jats:pIcons are integral to the signature systems within architectural spaces, serving pivotal roles through human–environment interactions. However, previous icon designs often exhibited a considerable randomness and neglected the needs of visually impaired individuals. To address these issues and to overcome the limitations of the computer-aided design methods, such as most of them focusing only on text design which are not compatible with icons, this study presents an intelligent assistance method named “Universal Colour” for icon colour design based on universal design principles. Such a system enables the rapid generation of icon colour schemes and supports visual and quantitative filtering and comparison during the decision-making process for colour scheme optimization. To assess its usability, fifty-two participants conducted icon colour design experiments using this system, resulting in 87% of the design schemes meeting the universality requirements. The results have demonstrated that Universal Colour has the potential to significantly enhance efficiency and cognitive aspects within the decision-making process for users, regardless of their proficiency in icon design, thereby facilitating the generation of universal icon colour schemes in architectural design.</jats:p>