An optimized facility layout design helps to ensure a high level of machine usability along with minimum cost and good performance. However, facility layout is a multi-objective design optimization problem, and as such, it is difficult to solve. This original research work aims to design an optimal linear machine sequence using particle swarm optimization algorithm that minimizes the following: the total investment cost of machines, the total number of machines in the final sequence, the total flow time of the products, and the total flow distance of the products. The effectiveness of the proposed algorithm is demonstrated with a reasonable number of problems. Maximum of 19.1% reduction in total flow distance of products, 12.8% reduction in total investment cost of machines, 28.4% reduction in total flow time of products, and reduction of two numbers of machines in the layout are achieved by proposed method compared with the previous approaches.