In this study a conventional rubber mount and a new form of base isolator made of steel spring coated with natural and articial rubber were manufactured and tested on a shaking table to investigate the capacity of reducing the vertical vibration of a building induced by subway train. The model structure used in the test is a 1/4 scaled steel structure, and a white noise input and train vibration records were used to check the effectiveness of the isolators. According to the results all three types of isolators turned out to perform effectively in reducing the acceleration and the natural rubber-coated one is ranked best among the isolators. However the vertical displacement of the model is increased due to the instolation of the bearings, and the safty against the lateral load induced by earthquake ground motion should be provided to be able to apply the system to the real buildings.