Starting from the propagation law of partially coherent light, spectral changes in Young′s two-slit experiment with Schell model beams are studied. That the spectral switches in Young′s experiment at far zone can also take place is pointed out. The spectral switch effect, which is physically attributed to the diffraction by the slits and spatial coherence of light, increases with increasing slit parameter ε and source spatial correlation Δ. Detailed numerical results are given to illustrate the behavior of spectral shifts and spectral switches in Young′s experiment and a comparison with previous work is also made.