Abstract: The chemical experiment device which can promote the reversible reaction has been introduced that combined with the preparative experiment of acetidin by the Le chateliers principle. The device referenced the industrial production method-reaction distillation method. It includes the dephlegmator, water separator, reflux device, and so on. The ester and the water can be steamed out of the system continuously, so it can promote the balance. Through the practice application, the product is less impurity, the subsequent refined is easy, the yield is higher. The experiment teaching effect is improved by the use of the device.