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Asphalt pavements are prone to cracking in low-temperature environments, and microwave heating (MH) can heal the cracks effectively. This research mainly investigates the different MH effects on the self-healing properties of asphalt mixtures. With this objective, the three-point splitting test is conducted to generate the cracks. A microwave oven is employed to heat the samples, and a thermal camera measures the surface temperature. Results indicate that heating power and time show a positive linear correlation with healing efficiency, and the <i>HI</i> of the samples can reach over 80%. The <i>HI</i> of the samples decreases with the heating cycle, but the sample with reasonable power and time still has a <i>HI</i> higher than 70% after 5 cycles. The temperature peaks on thermal images indicate that uneven heating exists during heating, but the heating uniformity is within an acceptable range. The healing efficiency level (<i>HEL</i>) suggests that asphalt mixtures have very low inefficient healing behavior if the heating time is below 45 s, but <i>HEL</i> can reach 86.14% at 700 W after 60 s. Furthermore, although the <i>HI</i> of strength shows ideal results, the recovery of other crack parameters, including stiffness, fracture energy, flexible index, and crack resistance index, are not satisfactory.