Linear low-density polyethylene (LLDPE) is one of the most important engineering thermoplastics due to its favorable combination of mechanical properties, good processability, and tunable molecular microstructure, which has secured its prominent position in polymer industries. LLDPE is primarily produced via copolymerization of ethylene with α-olefins in the presence of Ziegler–Natta or metallocene catalysts. In this study, a feasibility assessment of an LLDPE production plant with a nominal capacity of 400,000 tons/year was carried out. The estimated fixed capital investment, operating cost, and annual profit were 242.7, 363.7, and 156.3 million USD, respectively. Economic evaluation indicators, including an internal rate of return of 64.4%, a net present value of 518.5 million USD, and a payback period of 1.55 years at a 20% discount rate, demonstrate the economic viability of the project. Sensitivity analysis revealed that selling price and material cost exert the greatest influence on profitability, highlighting the critical role of market risk management in ensuring long-term economic sustainability.