The effects of different etching temperatures (near room temperature) on the length and surface morphology of SiNWs were reported in this paper. The studies on temperature dependence of SiNWs growth rate were carried out at 20 °C, 30 °C, 40 °C, 50 °C, 60 °C, and 70 °C for n-type and p-type substrates. The results suggested that the SiNWs length could be controlled easily by the change of the etching temperature. Superlong SiNWs were also fabricated by this technique. The superlong SiNWs had the length more than 400 μm and the aspect ratios were about 2000-20000, which could be applied in nanosensors and interconnection.