The aggregate selected for concrete in Xinjiang Dashixia water control project has alkaline activity, which may lead to the problem of alkali aggregate damage in project. The effects of local fly ash (FA) and ground granulated blast furnace slag (GGBFS) on alkali-silica reaction (ASR) were investigated. In addition, XRD and SEM-EDS were used to analyze hydration products and morphology of interface transition zone (ITZ). FA content ≥20% (mass fraction) or GGBFS content ≥40% (mass fraction) can significantly inhibit alkali-silica reaction. Amorphous phase is observed in interfacial transition zone of pure cement samples, and no amorphous phase is observed in samples containing FA or GGBFS, which means that the alkali-silica reaction occurs in pure cement samples. The addition of FA or GGBFS reduces the Ca/Si molar ratio of interfacial transition zone phase and inhibits alkali-silica reaction.