Thailand is the one of serious road accident counties in the world. Although there are many road safety
agents including government and non-government organizations try to solve and find better solutions for
Thai society but it seems the current road safety management system are not effective because the
accident situation is not improved. The key to support road safety management in all countries is an
accident data. This study found some accident data problems in Thailand such as accident underreport,
missing required data, non-map based location data. These data problems cause road safety management
problems. This study aims to improve accident database for support road safety management in Thailand.
The methodology of this study consists of review European and international experience, development of
accident data set, improvement of accident database. This study used VISUM Safety from PTV Company
to analyze some blackspot identifications. The main outcomes of this study are improved police accident
report and improved accident database for Thailand.