A method for landing an aircraft includes determining the aircraft's deviation from its approach path so as to define a first point of the aircraft's heading. A first straight line passing through the first point and through a second point defining the ground orientation of the approach path is displayed, by a head-up display, on a horizon line with a heading scale. The first straight line represents a ground plot of the approach path. A first assistance gate is displayed such that the first straight line passes through the first assistance gate when the aircraft is aligned on the approach path. A second straight line, parallel with the horizon line and passing through the first point, is displayed and represents a plot on the ground of the origin of the approach path. A second assistance gate is displayed under the horizon line and represents the slope of the approach path.