In this study, we investigated the effect of wire strength on wire sweep after the semiconductor transfer molding assembly process. The wire sweep, loop height, and tensile strength of 25μm, 20μm, and 15μm diameter wires were measured. As the tensile strength of 25μm wires is higher, wire sweeps have a tendency to become smaller with 4.7 mm loops. However, such a trend is not shown in the case of 15μm wires. It is found that the wire sweep of 15μm wires depends on the loop height when the loop length is more than 4 mm, and it depends on the wire tensile strength when the loop length is less than 4 mm.