This paper focuses on implementing particle swarm optimization (PSO) to optimize the robotic assembly line balancing (RALB) problems with an objective of maximizing line efficiency. By maximizing the line efficiency, industries tend to utilize their resources in an efficient manner. In this paper, two layout configurations of robotic assembly lines are proposed. In this robotic assembly line balancing problem, the tasks are assigned to the workstations and the efficient robots to perform the assigned tasks are chosen based on the objective of maximizing line efficiency. Performance of the proposed PSO algorithm is evaluated on benchmark problems and compared with the best known results reported in the literature. Computational time of the proposed algorithm is better than the one reported in the literature. Comparative studies on the performance of the two layouts are also done and the results are reported. © Springer International Publishing Switzerland 2016.