Broadband near-infrared (NIR) phosphors have received increasing attention for fabricating phosphor-converted light-emitting diodes (pc-LEDs) as NIR light source. Most of the reported broadband NIR phosphors originate from Cr3+ in weak crystal field environments. Herein, we report a luminescent material, MgAlSiN3:Mn2+ with CaAlSiN3-type structure, demonstrating that broadband deep-red-to-NIR emission can be achieved via doping Mn2+ into crystallographic sites with strong crystal field in inorganic solids. This phosphor is synthesizedviaeasy-handle solid-state reaction, and the optimized sample, (Mg0.93Mn0.07) AlSiN(3)shows an emission band with peak at similar to 754 nm, FWHM of 150 nm, and internal quantum efficiency of 70.1%. The photoluminescence intensity can further be enhanced by co-doping Eu(2+)as sensitizer. This work provides a new strategy for discovering new broadband NIR phosphors using Mn(2+)in strong crystal field as luminescence center.