Tm,Ho:LuAG crystal with high optical quality is grown successfully by the Czochralski method, and its spectroscopic characteristics are investigated. The absorption spectrum of Tm,Ho:LuAG crystal in the range of 320~3000 nm is measured, and a wide absorption band with full width at half maximum (FWHM) of 12 nm is located near 784 nm. The fluorescence spectrum in the range of 2800~3000 nm is measured by exciting with 784 nm laser diode (LD). The fluorescence decay curves are also measured by exciting with optical parameter oscillation (OPO) laser. The lifetimes of the upper lever 5I6 (51 μs) and lower lever 5I7 (7.5 ms) are obtained by fitting the exponential decay curves. Compared with the parameters of Tm,HoYAG (Y3Al5O12) crystal, it suggests that Tm,Ho:LuAG crystal is a potential mid-infrared laser material to realize the laser at 2.911 μm.