In recent years, the luminescence properties of the rare earth ions-doped nanocrystals become more and more popular because the rare earth luminescent nanocrystals have important applications in photoluminescence, high-definition display, optoelectronic nano-devices, biological labeling, laser and scintillator etc.. In this project, a series of different particle size, dispersion, controllable morphology rare earth ions-doped oxide(fluoride) micro-/nano-crystals were synthesized by soft chemistry synthesis method such as hydrothermal, sol-gel method et al.. The luminescence properties were investigated by excitation spectra, emission spectra, diffuse reflectance spectra and high-resolution laser spectra in order to observe the changes of luminescent phenomenon with different size and chemical bond. The essential reason of the impact of luminescence behavior was also investigated by summary and classification. At the same time, theoretical calculations of optical properties were performed by using density functional theory and complex crystal dielectric theory of chemical bond method with the combination of spectral experimental data, which can successfully explain the spectral shift rule and energy transfer mechanism between the different rare earth ions. The results can lay the theoretical and experimental basis for the other rare earth spectroscopy.