Green entrepreneurship (GE) has recently become one of the important factors in attaining competitive advantages and a firm's sustainability, while Human Capital (HC) is the facilitator of our growth, prosperity and progress. The meaning and role of this small word, green, is so significant that our lives and the future depend on it. However, the implications of GE for HC and Business Sustainability (BS) are still unclear. This empirical study investigates several aspects of GE, HC and BS: first, the relationship between GE on HC and BS in Malaysian Large Manufacturing Firm (LMF); and secondly the mediating role of HC on the relationship between GE and BS. A research model was developed to test these hypothesized relationships. The model was tested on data from 213 Malaysian LMFs, employing structural equation modeling (PLS-SEM). GE has a significant effect on HC and BS. HC has a significant effect on the BS of LMFs in Malaysia, and fully mediates the relationship between GE and BS. The results provide useful insights for researchers and managers of manufacturing firms, and the paper outlines the practical and theoretical implications and potential future research.