Despite the growing importance of the concept of circular economy, the case of developing countries remains under-explored. Against this backdrop, the present research aims to examine the association between the constructs of total quality management (TQM) and organizational sustainability (OS) with the mediating effect of knowledge management (KM) from the perspective of a circular economy. The data were collected from the manufacturing sector of a developing economy (n = 510) to serve the purpose of the current research through a self-administered questionnaire (paper-pencil technique). Structural equation modeling (SEM) was employed for hypothesis testing of the current survey. Six TQM dimensions were drawn from the Malcolm Baldridge National Quality Award (MBNQA) model. OS is composed of economic, social, and environmental sustainability, and KM is composed of four dimensions including acquisition, creation, sharing, and application of knowledge. The empirical examination suggests that TQM positively relates to OS, with KM playing a partial mediation role between this association. This study provides important insights for the management of the manufacturing industry of Pakistan on how to ensure organizational sustainability in the age of a circular economy by using the constructs of TQM and KM.