In today's competitive environments, companies need to be cost-effective, environmental-friendly, and social-friendly to deal with several challenges that exist in markets. In this context, reconfigurable manufacturing systems (RMSs) have emerged to fulfil these requirements. RMS is one of the attractive manufacturing paradigms. Machine components, software, or material handling units can be added, removed, modified, or interchanged as needed and imposed by the necessity to react rapidly and cost-effectively to changing. A multi-objective multi-product process and production planning problem in a sustainable reconfigurable manufacturing environment (SRMS) is considered in this paper. Three pillars of sustainability, respectively social, environmental, and economic are formulated and optimised. First, a linear mixed-integer model is proposed. Second, a Lagrangian relaxation-based approach is developed to solve the problem on the large scales, where an exact method is used to solve the problem in small and medium cases with GAMS software. To illustrate the applicability of the proposed approaches, some numerical examples and analyses are presented. Finally, a sensibility study of the problem according to some parameters is performed.