Today, we are living in the knowledge century. Knowledge-based intangible resources in enhancing sustainable growth of small and medium enterprises (SMEs) is presently a significant scope of research. Innovation capability is the intuitive skill of an individual or a firm to transform an explicit concept towards value orientation that carries an economic value. This economic value would then lead to wealth creation and eventually result in sustainable SMEs. The SME sector has been highlighted for its significant contribution towards the creation of employment, opportunity for innovation and economic dynamism. In this study, evidence derived from knowledge-based view and knowledge creation theory was used to construct a structured model to analyze the relationships among innovation capability, disruptive technology and knowledge creation and their impacts on SMEs sustainability. A sample of 384 owners of SMEs in Sri Lanka was included in the study. The outcome of structural equation modelling (SEM) discovered positive effects of innovation capability, disruptive technology and knowledge creation on sustainability. Innovation capability also emerged as a predictor of disruptive technology and knowledge creation. Moreover, disruptive technology and knowledge creation were found to be partial mediators of the association between innovation capability and SMEs’ sustainability. These findings pave the way for policy makers to promote sustainability in SMEs, by assisting to enhance their performance in competitive and innovative economic environments. Further, the validated model can be empirically tested in future research.