In order to explore the significance of X-ray pulsar spectra for X-ray pulsar navigation, an X-ray pulsar energy simulation method was proposed. In this paper, X-ray tube was used to produce X-ray signals, and emission spectroscopy was controlled with anode voltage. To achieve X-ray pulsar spectrum simulation, least squares was used to obtain anode voltage curve, and then ground experiment was realized. Mathematical modeling and simulation were implemented, and the corresponding results prove the feasibility of this method. Furthermore, ground experiments were carried out, experimental results show that the similarity of X-ray pulsar spectra between experimental and actual is almost 79%. In addition, a scheme of simulating X-ray pulsar energy and flow simultaneously was proposed based on above energy simulation. These works can provide an experimental platform for future X-ray detector and navigation algorithm.