La2MgTiO6∶Mn4+, La2MgTiO6∶Pr3+, La2MgTiO6∶Pr3+, Mn4+ single-doped and co-doped phosphors were synthesized by high-temperature solid-state method. The phase structure, morphology, and luminescence properties of the phosphors were characterized and analyzed by means of X-ray diffraction, scanning electron microscopy, and fluorescence spectrophotometer. The results show that, La2MgTiO6∶Mn4+, La2MgTiO6∶Pr3+, La2MgTiO6∶Pr3+, Mn4+ phosphors with pure phase were successfully synthesized. The particle size of the samples is 1~2 μm. The red emission of La2MgTiO6∶Mn4+ at 650~750 nm is attributed to the 2Eg→4A2g transition of Mn4+. La2MgTiO6∶Pr3+ exhibits strong emission in the red light range between 600 nm and 660 nm, which is attributed to the 3P0→3H6 and 3P0→3F2 transition of Pr3+. Because of the different red light emission regions of Mn4+and Pr3+, when they are co-doped in La2MgTiO6, the emission spectra of the co-doped phosphors closely match with the absorption spectra of phytochromes Pr and Pfr. The results indicate that, compared to the single-doped phosphors, the red light emission region of the Mn4+, Pr3+ co-doped phosphors are widely extended. The red light emission region of the co-doped phosphors are more tally with the needs for plants grow. The La2MgTiO6∶Pr3+, Mn4+ phosphors has potential application in LED plant illumination.