The resistive interchange instability of an incompressible plasma is investigated for the plane sheet pinch taking into account of the equilibrium diffusive flow effect. We derive the reduced resistive MHD equations including this effect and study the stability utilizing both numerical and analytical methods. The results are compared with the existing theory in which the equilibrium diffusive flow is not considered. In particular, we find that the effect of diffusion flow stabilizes the resistive interchange modes in the short-wavelength limit.
