The effect of magnetic fields on black hole superradiance is an interesting topic with possible astrophysical applications. A dyonic RN-like black hole is not asymptotically flat, it describes a black hole immersed in an asymptotically uniform magnetic field. In this paper, we discuss the superadditive stability of a class of asymptotically flat, band-like black holes, the binary RN black holes. In this article, we introduce the above condition into dyonic RN-like black holes. If a dyonic RN-like black hole satisfies the condition of µ = yω, when µ ≥ √ 2(mΩH + qΦH),so the dyonic RN-like black hole is superradiantly stable at that time.