Non-dominated Sorting Genetic Algorithm III (NSGA-III) is a multi-objective algorithm which uses reference points in generating the n-dimensional vector space in order to find the set of objective functions which is the shortest perpendicular distance to each of them. The purpose of the research is to compare the performance of NSGA III and MOEA/D on the worker allocation problem on multiple cellular U-shaped assembly lines attempting to realize five objectives, i.e. minimizing idle worker, minimizing number of workers, maximizing utilization of workers, minimizing walking time and minimizing the deviation of walking time. The experiments showed that NSGA-III performs better than MOEA/D in terms of convergence to Pareto optimal set, convergence and diversity metrics and ratio of Non-dominated Solutions.