In this paper, alkali silica reactivity of chert and siliceous slate was investigated, and petrographic examination of these rocks was carried out. Petrological characteristics, JIS A1145 chemical method and mortar-bar method were examined on chert rock and siliceous slate which were included in the ASR damaged concrete structure in Aichi Prefecture. In the expansive test method of mortar and concrete, storage environment was changed in various types of conditions. The results of the chemical method became innocuousness, when the crystallinity index measured with X-ray diffraction exceeded 7.5. And in the JIS A1146 mortar bar method, the expansion of mortar made with chert and siliceous slate exceeded 0.1% in 2 months, and in comparison with both rock, the expansion of mortar using siliceous slate was higher than that of mortar using chert. Furthermore, the expansion of the mortar bar of the mixing use of siliceous slate and chert was higher than that of the single use.