The near-infrared fluorescent powder with broadband emission and its preparation method and application belong to the technical field of luminescent materials. The problem that the bandwidth of the infrared light emitted by the infrared LED and the infrared laser in the prior art is very narrow is solved. Near infrared fluorescent powder of the present invention, chemical formula is: (R a ln b Ce c Cr d )(L e Cr g )(M k B m Cr n )O 12 ; In the formula, R is Ca 2+ 、Sr 2+ 、Ba 2+ One or more of, Ln is Lu 3+ , Y 3+ , La 3+ 、Gd 3+ One or more of, L is Hf 4+ and / or Zr 4+ , M is Al 3+ and / or Ga 3+ , B is Si 4+ and / or Ge 4+ ; a, b, c, d, e, g, k, m and n are all element mole fractions. The near-infrared phosphor can be used as a light conversion material for near-ultraviolet LED chips, blue-light LED chips and red-light LED chips to realize a near-infrared light source with broadband emission.