Road accident is an undesirable event that causes injuries and material damage. Recently in Indonesia, the increasing trend of road accidents has caused significant damage in fatalities and infrastructure. In order to reduce the number of road accidents, necessary information is required so decision-makers could take action. Data mining offers technique to analyze extensive data which is advantageous due to road accident heterogeneous nature. The clustering method is used to group data in order to reduce heterogeneity, and association rule mining method is used to find common characteristics of each clusters. There are thirteen clusters found. Each clusters are analyzed further using association method. The data used in this research is Highway accident in Cikopo-Palimanan Toll road 2017-2019.