Nanosilica is nano-sized silica, which is around 1-100 nm and has a function to increase the compressive strength of concrete. Nanosilica can be produced by the extraction process from palm oil fuel ash waste. The materials used in this study were palm oil fuel ash and high energy milling as a grinding tool. This study used variations in grinding time for 1, 3, and 5 hours. This study used micr…