Medical three-way valves are commonly used in conjunction with other medical devices. They are widely used in medical field as intravenous injection or transfusion for human body. At present, three-way valves commonly used in medical clinic usually include a manual knob to control the closure and opening of the pipeline manually. Because the manual operation process is cumbersome and error-prone, it brings great potential safety hazards to medical work. Later, a kind of medical three-way valve with one-way automatic control appeared on the market, which included the main body of the three-way valve. The main body of the three-way valve was equipped with an intake channel and a drainage channel, and the intake channel and the drainage channel were equipped with a plug. The plug was covered with a spring that elastically applied the plug to the intake port of the intake channel and the intake port of the drainage channel. By pulling and pushing the syringe, the liquid inlet of the intake channel and the discharge channel can be opened separately in turn to prevent the liquid from flowing back from the discharge channel to the intake channel, so as to achieve the purpose of one-way automatic control. However, the spring will sway or shift during the deformation process, which will easily cause uneven force exertion, and then cause loss between the main body of the three-way valve and the spring, as well as between the plug and the spring. The debris produced by wear and tear will pollute the liquid medicine, thus endangering human health.