The absorption spectra of Tm 3 + :KGd(WO 4 ) 2 crystal in three mutually perpendicular arbitrary directions at room temperature were measured. Based on Judd-Ofelt theory and TPM method, the intensity parameters Ω t (t=2,4,6), the radiative lifetimes, the experimental and theoretical oscillation strengths, and the fluorescence branching ratios were obtained. The broad emission spectrum from 1650 to 2000 nm was obtained under 800 nm excitation. Also, the fluorescence spectra at 455 and 665 nm were measured under 360 nm excitation. Their stimulated emission cross-sections were also calculated.