A ray-tracing algorithm of the elliptical reflection zone plate (ERZP) based on the grating diffraction theory is proposed, and the diffractive focusing and spectrally resolved properties of an ERZP are analyzed. Based on the proposed algorithm, the ERZP ray-tracing module is added in the optical simulation software X-LAB, which makes it possess the advantages of small computational cost and high efficiency. This is of great significance to the design and numerical simulation of optical systems with an ERZP.