Abstract: In this paper,we introduce and devise Non-dominated Sorting Genetic Algorithm (NSGA-II) for solving the constrained multipath traffic engineering problem in GMPLS optical networks.A formulation of this problem as a multiobjective constrained optimization is first extended.Then,we develop a hybrid heuristic algorithm based on linear programming.We also compare the performance of the proposed heuristic using a similar problem adopted from the literature with the exact solutions generated using a lexicographic Chebyshev method.