A method of determining topographical interference with a guided missile is proposed. The method may include obtaining a pre-calculated expected trajectory of a guided missile. The method may also include extracting topographic elevations with respect to a topography corresponding to the pre-calculated expected trajectory from stored topographical information. The method may further include determining presence or absence of topographical interference with the guided missile based on bottom trajectory elevation values in the pre-calculated expected trajectory and topographic elevation values corresponding to the bottom trajectory elevation values. The pre-calculated expected trajectory may include top, bottom, left, and right trajectories with respect to a launch direction of the guided missile, calculated based on an error factor for the guided missile, and the error factor includes manufacturing error values with respect to at least one of a weight, center of gravity, a thrust, or a moment of inertia of the guided missile.