Global environmental issues are becoming increasingly severe. They include a number of problems, such as global warning effects, depletion of ozone layer, acid rains, desertification and Endocrine Disrupting Chemicals (EDC), etc. Industries and the public at large have recognized that they should decrease environmental loads from their own positions to solve these problems. To do this, it is required to assess the present conditions first and establish a method to grasp the entire environmental loads in quantitative terms. Life Cycle Assessment (LCA), which is to quantitatively assess the environmental loads of products or services through their lifetime, is now under development for this purpose. Standardization of this method is in progress in one of the ISO 14000 series concerning the environmental management and audit system, but LCA hasn't completely been established yet. Especially, issues still under examination and discussion include incomplete basic data, required to calculate environmental loads and a method to assess the total load. It is indispensable for railways as well, to introduce LCA in order to reduce environmental loads.