Asian mega cities have continued to expand, and accordingly, various problems, e.g. social, economical and environmental problems, have been widely recognized in Asia. Especially, environmental issues caused by Asian mega cities will affect not only the areas within mega cities but also the whole area of Asian countries because the effects will be widely propagated by atmospheric or marine transportation. Authors have conducted researches related to comprehensive assessment indices for urban sustainability, named as Environmental Indices for Urban Sustainability (EIUS). In the framework of EIUS, both the environmental quality and the environmental load are focused on. An urban sustainability will be evaluated based on the scores for all categories of EIUS . Most of the environmental data used in EIUS are collected from statistical data and those are restricted to point-based data. If area-based data such as vegetation distribution or urban area distribution are required, remotely sensed technique is quite useful. Remote sensing data also has an advantage to compare the parameters of different cities by the same criteria. In the present research, the applicability of remote sensing data to extract area-based environmental data for EIUS was examined. Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) images, observed in 1990s and 2000s, were used to extract vegetation index, albedo and land surface temperature. Urban areas of Bangkok in 1990s and 2000s were extracted from such parameters. Based on the acquired results, the methodology will be improved and applied to extract urban areas in other Asian mega cities.