In this paper, the Gray Wolf (GWO) algorithm has been used to design and to optimize the geometrical parameters of broadband compact silicon on insulator waveguide crossing structure operating in the wavelength range of 1400–1600 nm. The electromagnetic numerical simulations of the waveguide crossing have been conducted by using an efficient frequency domain finite element (FEM) approach. The objective function is based on the maximization of the transferred power while minimizing the crosstalk. The performance of the optimization algorithm has been assessed by adjusting the number and the initial position of the wolves. Coupling efficiency higher than 96% has been obtained. Moreover, a tolerance error analysis has been carried out for the best crossing configurations to investigate their robustness.