This paper evaluates the affection of steel slag in the asphalt mixtures for the self-healing purpose through microwave heating technique. Four different contents of steel wool fibers (SWF) were developed in hot mix asphalt and two types of aggregate were used: steel slag aggregate and normal aggregate. By using the infrared camera, the thermal distribution, as well as the optimum healing time of test samples, were recorded. All mixtures were evaluated their healing performance throughout 8 cycles. The substitution of about 30% normal coarse aggregate by steel slag is prominent due to its effect not only produces better healing performance but also enhances the whole mixture improve load-displacement trend with higher ductile behavior. The application of steel slag in HMA is a promising method which contributes toward the sustainable roadway development.