The invention relates to a preparation method of an ultra-fine-crystal high-toughness heat-resistant aluminum alloy lead. The preparation method comprises the following steps: (1) performing proportioning, wherein the aluminum alloy lead consists of the following components in parts by weight: 100 parts of industrial pure aluminum, 0.7 part of aluminum-zirconium alloy, 0.4 part of aluminum-copperalloy, 0.4 part of aluminum-erbium alloy, 0.0015 part of a refiner Al-5Ti-B, 0.06 part of a modifier Sr and 0.5 part of a refining agent hexachloroethane; (2) performing smelting: adding pure aluminuminto a coreless medium-frequency induction furnace, increasing the furnace temperature to 740 DEG C, starting ultrasonic vibration for 20 seconds when the temperature reaches 720 DEG C, adding intermediate alloy, a modifying agent and a refining agent by a bell pressing method after the metal is completely melted, wherein electromagnetic stirring is carried out during the adding process, and thenperforming refining and slagging off; and (3) casting prepared alloy liquid into ingots, then performing multi-directional forging on the alloy ingots, and performing homogenization treatment, rolling, stress removal annealing, low-temperature continuous equal channel angular processing (ECAP), precipitation strengthening, drawing and twisting.