The invention relates to a preparation method for Al-Cu alloy round aluminum rod. The invention is characterized in that the method includes the following steps: (1) loading aluminum liquid with aluminum content of above 99.5%, controlling temperature thereof at 780-800 DEG C; (2) adding copper to control copper content between 0.35% and 0.8%, keeping the temperature at 780-800 DEG C for more than two hours, stirring at the same time; (3) adding silicon and iron into the aluminum liquid in the step (2), with silicon content controlled below 0.1% and iron content controlled below 0.4%, appropriately mixing after adding, and then melting, continuous casting and continuous rolling, thus Al-Cu alloy round aluminum rod is obtained. Compared with the ordinary pure round aluminum rod for electrical purpose, the maximum tensile strength of the inventive Al-Cu alloy round aluminum rod is improved by about 15% and the corresponding elongation is increased by over 30%, while the resistance rate is almost kept the same.