Quantum-dot fiber has gradually become a research focus in optical communication field. This paper first introduces the development history of the CdSe/ZnS quantun-dot doped fiber. Whereafter, the preparation method of the CdSe/ZnS quantun-dot doped fiber with two kinds of different backgrounds is discussed. The spectral properties and peak gain of the photoluminescence are then comparatively analyzed. Finally, through the analysis we can get the proper background for CdSe/ZnS quantun-dot doped fiber. This research can give some useful experiences for developing other quantum-dot doped fiber.