Abstract: The CsPF₆:Mn⁴⁺phosphor was synthesized via a facile co-precipitation route. The effects of introducing cations Li⁺, Na⁺ and K⁺ into CsPF₆: Mn⁴⁺ phosphor on the luminous intensity were studied. The prepared phosphor samples were all in pure phases. Under blue light excitation, a series of sharp red emission lines appeared, which peaked at 634 nm. After doping with K⁺ and Li⁺, the emission intensities increased, but after doping with Na⁺, the emission intensity decreased. Among them, the luminescence intensity of CsPF₆:Mn⁴⁺ phosphor with the addition of K ion was the strongest. The emission intensity of CsPF₆:Mn⁴⁺ phosphor first increased with the rise of temperature and then decreased with the increase of non-radiation transition. It reached its maximum value at 423 K, and the emission intensity also increased, compared with that of phosphors without cation introduction. It is proved that the introduction of cation can effectively improve the luminescence performance of CsPF₆:Mn⁴⁺ phosphor.