Aluminum is widely used and recognized as the best material in a variety of uses in various sectors such as automotive, construction, aircraft, and others. However, its strength is still low, including its wear resistance. The purpose of this study was to determine the effect of adding rice husk ash to the hardness and microstructure of aluminum. Using the evaporative casting method with variations in the ratio of aluminum and rice husk ash (100% : 0%), (97.5% : 2.5%) and (95% : 5%) and the variation of the casting temperature is 650°C, 675°C and 700°C. Hardness testing using a portable digital hardness tester Mitech MH600 and microstructure observations using a USB digital microscope with 800X magnification.