We report on an experimental study on the wavelength-scaling law of elliptical-polarization dependence of high-order harmonic generation. In the elliptical-polarization dependence measurements, we keep an identical peak intensity for pump pulses with carrier wavelength ranging from $800\mathrm{nm}$ to the mid-IR region, and the harmonic emission near the cutoff region is selected for comparison. We find that the experimental measured wavelength scaling of elliptical-polarization dependence could be well fitted with a function $({\epsilon }_{1∕2}\propto {\lambda }^{-1})$ predicted by semiclassical model.