Abstract: To ensure the accuracy of tube voltage of X-ray machine, voltage compensation for X-tube is essential. But its principle is complex and abstract. X-ray machines used in clinical practice haven’t functions of displaying compensation principle and compensation effect, so it is difficult to use for experimental teaching. Due to the lack of necessary experimental equipment, principles of voltage compensation circuits and compensation algorithms have become difficult points of the teaching of medical imaging equipment. In order to solve the problem and improve the teaching quality, an experimental device for X-tube voltage compensation has been designed in this paper. The experimental device for X-tube voltage compensation designed in this paper can vividly demonstrate the difference of voltage values before and after compensation. By doing so, the principle of X-tube voltage compensation and factors affecting the accuracy of compensation can be demonstrated in a simple and clear way. So it is helpful for students to understand the principle and effect of voltage compensation essentially. In addition, the experimental device also has advantages like simple structure, simple operation and convenient demonstration. In a word, this experimental device has practical value and is worth popularizing.