To enable a fine control of particles dispersed in a polymer alloy by melt-keading at least two non-compatible thermoplastic resins through chaotic mixing.

The polymer alloy includes a dispersion structure in which the particles dispersed in the polymer alloy have an average particle diameter of 0.001-1 m, and gives, in scattering analysis, a spectrum that is a plot of the intensity of scattered light against the wavenumber of scattered light, the spectrum satisfying 0<(a)/(b)≤1.5, where (a) is the half-value width of a peak in the spectrum and (b) is the maximum wavenumber at the peak. This polymer alloy gives a molded article which retains the excellent heat resistance and mechanical properties that are inherent in the compounding resins and which further has transparency.