The beamhouse plays a pivotal role in leather manufacturing. However, the conventional lime-sulfide system (LSS) used in the beamhouse causes significant environmental pollution due to the extensive use of chemical agents. In recent years, most research has focused on biological treatments, with enzymes emerging as a promising environmentally friendly alternative. In this study, we employed the salt-enzyme system (SES) to utilize MgCl2-assisted neutral protease to streamline processes and reduce pollution in the beamhouse. Additionally, response surface methodology (RSM) was utilized to optimize the experimental conditions for enhancing unhairing, fiber opening, and bating efficiency. In terms of environmental benefits, compared to LSS, SES exhibits a significant decrease in COD, NH3-N, and TS by 9.59%, 26.27%, and 76.94%, respectively, highlighting its efficacy as an environmentally sustainable alternative. The environmental impacts of the beamhouse stage (LCA) approach by comparing two scenarios. The results showed that all the environmental significantly lower than those linked to LSS. The utilization of MgCl2-assisted neutral protease in a one-step beamhouse aligns with the trend of environmentally friendly and green production for the leather industry.