Due to the unique fluorescence characteristics, superstructures from self-assembly of semiconductor nanoparticles have become essential components of material and chemical science, and thus it has broad application potential in displays, single-photon source, sensing, biological tagging and emerging quantum technologies. Superstructure refers to an artificial functional architecture whose length scale is between the quantum scale and the macroscale. When solely treating this complicated stage fitted from less complicated pieces together (basic nanoparticles) and pile speculation on speculation, we must understand the fundamental questions, that is, what the hierarchy or specialization of function is at the stage. The uniqueness of this stage is not the collection of basic nanoparticles, but the behavior that emerges on fluorescence-basically a new type of behavior. Under the angle of view, this study reviews the advances in the fluorescence of individual semiconductor nanoparticles, inter-nanoparticles coupling and thus emergent fluorescence behaviors of assemblies. We also try to present the methodology for seeking emergent behaviors on fluorescence.