The main purpose of this study is to investigate the relationships between employees’ perceptions of sustainability performance and their internal brand commitment in industrial markets. The study was conducted among employees holding top and middle management positions in industrial companies in Belarus. 238 responses were analyzed by using the independent samples t-test, and the K-means cluster analysis. ANOVA was utilized for evaluating the differences between the three identified clusters. The findings of this study indicate the presence of significant differences in perceptions of employees assigning various degrees of importance to sustainability in relation to their evaluations of company’s sustainability performance and the key determinants of internal brand commitment. Furthermore, the study assesses the profiles of three alternative clusters of employees characterized by various degrees of importance assigned to sustainability, and by different levels of internal brand commitment. The study proposes practical recommendations for marketing managers and HR managers on how to utilize internal branding for enhancing awareness of employees about the importance of sustainability, and for facilitating positive perceptions about sustainability performance of their respective companies.