A quick algorithm for locating the ghost coordinates in high-power laser systems is presented for analyzing multi-reflection and multi-order diffraction ghosts in design so as to avoid damaging the systems. The primary paraxial ray and chief ray are traced and saved in a multi-pork tree expressed as a binary tree at the same time, the z coordianate zg of each ghost is determined by tracing the primary paraxial ray, and the intersection point of the chief ray and the plane z=zg is regarded as the position of the real ghost. Taking a tilt lens and the final optical assembly (FOA) with a diffraction optical component as examples, the space coordinates of some ghosts are predicted. Certified by high-density real ray tracing, optical energy is focused at the predictive position in corresponding ghost plane. The results show that the predicted ghost point is coincident with the area at which the real rays condense. The positions of 13124 ghosts in a laser system including 222 surfaces are found in 16 s using this algorithm.