The invention discloses technology for casting and forging an aluminum alloy connecting rod, wherein an aluminum alloy composition of the connecting rod is adjusted by addition of rare earth element in casting technology, and the addition of the rare earth element is 2 to 5 percent of an aluminum liquid; the aluminum alloy connecting rod is guaranteed to comprise the following compositions: 88 to 94 percent of aluminum, 3.8 to 4.9 percent of copper, 0.5 to 1.5 percent of silicon, 0.4 to 1.2 percent of manganese, 0.4 to 1.0 percent of magnesium, 0.8 to 1.8 percent of rhenium and 0.4 to 0.14 percent of iron; and a casting head is not cut off and reheated in the casting technology and taken as one part or a scrapped part of a forged piece, and casting afterheat is utilized for forging. The technology simplifies the prior die forging technology, improves reasonable floatation, the streamline and mechanical properties of casting metals, improves a metallurgical structure close to the casting head on the forged piece, and has the effects of high technological utilization rate of materials, shortened technological process and energy conservation and consumption reduction. Moreover, the casting and forging technology can obviously improve the internal quality and the mechanical properties of casting blanks, and the production cost of the casting blanks is lower than that of the prior die forging.