Cruise missiles (CMs) are getting more advanced. To cope with the rapidly growing CM threat, national air-defense systems use surface-to-air missiles (SAMs) as interceptors. To intercept a CM with a SAM, an optimal guidance law should be used. Simulations that represent reality as closely as possible show the effectiveness of the missile system in various scenarios. A three-degree-of-freedom, discrete-time, and three-dimensional simulation model that compares proportional navigation (PN), augmented proportional navigation (APN), and differential geometry (DG) guidance laws against a maneuvering and non-maneuvering CM that flies at low altitude and constant speed is described. Simulation results were obtained for two cases: ideal measurements and Kalman filtered noisy line-of-sight angle (azimuth and elevation) and range measurements. Noise tolerance was also examined to determine the best guidance law. For the simulation scenarios, targets are simulated at all aspect angles and for various ranges. The results show that for a non-maneuvering CM, all three guidance laws give similar results. Against maneuvering targets, DG is better for tail-chase scenarios and PN is better for the forward quadrant of aspect angles. APN performed poorly compared to the other guidance laws examined in these scenarios.