Modular construction uses pre-fabricated volumetric units that are transported and installed on site as fitted-out and serviced 'building blocks'. The use of modular construction is directly influenced by the client's requirements for speed of construction, quality, reuse and benefits of economy. These benefits may be maximized under the condition that modules are almost manufactured in factory and transported to the site without any damages. In Korea, some damaged modules were reported on the process of transportation. This paper quantifies the vibration performances of modular units under transportation by analytical and experimental methods. Quantified vibration performances are reflected to the transportation guide of modular units.