For the favorable physicochemical properties, high fluorescence conversion efficiencies, a relatively short fluorescence lifetime, and an efficient spectral congruence between excitation and ultraviolet/blue LED emission spectra, Ce3+-doped garnet-based fluorescent materials can be used in encompassing lighting, displays, medical imaging, etc.. For leveraging the diverse cation sites within a garnet structure, the emission wavelength of Ce3+ can be continuously adjusted from 460 nm to 610 nm via the incorporation of varied matrix chemical constituents. This versatile tunability broadens the horizons of their potential applications and augments the repertoire of materials available for advancing Ce3+ luminescence theory. However, recent work on Ce3+-doped garnet-based fluorescent materials has unveiled certain anomalies and even contradictions within the characteristics and the emission wavelength modulation theory, becoming one of the prominent bottlenecks hindering the development of this material. To address this issue, this review represented the relative theories of substrate chemical component substitution and the modulation of Ce3+ emission wavelengths. The review also summarized recent advancements in Ce3+-doped garnet-based fluorescent materials, and the influence of ion substitution on Ce3+ luminescence performance with the distortion factor of [CeO8]. This review discussed the Ce3+-doped yttrium aluminum garnet structure as a prototype and comprehensively analyzed the impacts of commonly used doping ions that occupy the [AO8], [BO6], and [CO4] sites on the emission wavelength, thermal quenching resistance, and the [CeO8] distortion factor of Ce3+.The ion substitution of a single lattice generally necessitates that the substituting ion and the substituted ion have the same valence state and exhibit a minimal disparity in atomic radius. In the case of [AO8] lattice substitution, Y3+ can be replaced with rare-earth ions, i.e., Lu3+, Tb3+, Gd3+, and La3+. When the radius of the doped rare-earth ions is greater that that of Y3+, the emission wavelength of Ce3+ shifts towards the red end of the spectrum. Conversely, when the radius is smaller, the shift occurs in the opposite direction. The ion substitution of octahedral lattice sites mainly involves the replacement of Al3+ by Ga3+, Sc3+, and In3+. With an escalation in the concentration of doped ions like Ga3+, Sc3+, and In3+, the peak wavelength of the Ce3+ emission spectrum has a blue shift. In addition, the incorporation of Sc3+ effectively enhances the thermal quenching resistance of Ce3+, while the inclusion of Ga3+ diminishes the thermal quenching resistance of Ce3+. The main substitutions of dodecahedral-octahedral lattice ion pairs include Ca2+-Hf4+ and Ca2+-Zr4+ replacing Y3+-Al3+. The emission and excitation peak wavelengths of Ce3+ gradually blueshifts as Ca2+-Hf4+ and Ca2+-Zr4+ doping contents increase. The substitution of dodecahedral-tetrahedral lattice ions is mainly achieved by M2+-Si4+ (M=Mg, Ca, Sr, Ba) replacing Y3+-Al3+, with alkaline earth metals occupying the dodecahedral lattice and Si4+ occupying the tetrahedral lattice. In the garnet system, when M2+-Si4+replaces Y3+-Al3+, the emission wavelength of Ce3+ undergoes a blue shift with the increase of M2+ ion radius, resulting in improving the thermal stability. The substitution of octahedral-tetrahedral lattice ions mainly involves Mg2+-Si4+/Ge4+ replacing Al3+-Al3+, where Mg2+ occupies the octahedral lattice and Si4+/Ge4+ occupies the tetrahedral lattice. Among them, Mg2+-Si4+ replacing Al3+-Al3+ is an effective method to achieve a large redshift of Ce3+ emission wavelength. The introduction of Mg2+-Ge4+ also leads to the redshift of Ce3+ emission wavelength, but the extent of this redshift is considerably less than that achieved by Mg2+-Si4+. The chemical components in dodecahedral-octahedral-tetrahedral lattice co-substitutions are more intricate, with Ca2+ and Mg2+ occupying the dodecahedral lattice, Mg2+, Sc3+, and Hf4+ occupying the octahedral lattice, and Si4+ and Ge4+ in the tetrahedral lattice. Different lattice ions on the co-substitution affect the luminescence performance of Ce3+.Summary and prospects The effect of ion substitution on the luminescence performance of Ce3+ is analyzed via utilizing Ce3+-doped yttrium aluminum garnet fluorescent material as a prototype. The comparative study reveals that the most effective redshift of Ce3+ emission wavelength appears when Mg2+-Si4+ occupies the octahedral-tetrahedral lattice configuration. This results in a possibility of red shifting the emission wavelength of Ce3+ at 610 nm, thereby significantly enhancing the color rendering capabilities of white LED/LD lighting systems. Conversely, an effective blue shift in Ce3+ emission wavelength appears in Ca2+-Zr4+ located in the dodecahedral-octahedral lattice, with a potential shifting at 460 nm. Furthermore, the inclusion of Sc3+ in the octahedral lattice and Ba2+-Si4+ in the dodecahedral-tetrahedral lattice markedly improves the thermal quenching resistance of Ce3+. Hence, this combination exhibits substantial advantages for high-power LED and LD lighting applications. In contrast, the introduction of Ca2+-Mg2+-Si4+/Ge4+ into the dodecahedral-octahedral-tetrahedral lattice configuration leads to a poor thermal quenching resistance for Ce3+, indicating a unsuitability for white light LED/LD illumination.Furthermore, the d88/d81 ratio is related to the Ce3+ emission wavelength and thermal stability, based on the degree of [CeO8] distortion. It is indicated that at an equivalent Ce3+ doping concentration, an increase in the d88/d81 ratio corresponds to a redshift in emission wavelength and a decrease in thermal stability. Among the research results available, little work on the impact of d88/d81 value on the luminescence performance has been done yet. A future research on the in-depth physical models and subsequent experimental validation for Ce3+-doped garnet-based fluorescent materials is needed.