MLCA (materials environmental life cycle analysis), an established assessment measure of ECOMATERIALS, is a promising method to quantitatively assess materials with regard to environmental burden and to provide parameters for materials design with consideration of environmental affects. The data of environmental burdens, i.e., energy consumption, resource consumption, CO₂ emission, SO_X emission, etc., are collected in all stages of material life. From these data, the environmental burden of metals and alloys are calculated and arranged with a detailed description of the alloys, such as 12Cr steel, 18Cr8Ni steel, etc., in a database named Materials Eco-Sheet. Eco-Sheet provides the parameters of environmental load and gives the quantitative relationship between the properties of a material and its environmental load by use with a database of mechanical or other properties of materials.