With the help of absorption and fluorescence spectra, the spectroscopic properties of Tm3＋, Ho3＋:YVO4 crystalshave been investigated under different dopant concentrations. The absorption results show that the maximum absorptionin the spectral range of currently available powerful laser diodes (LD) is at 796 nm, corresponding to the transition3H6 →3H4 of Tm3＋ in the crystals. Upon the excitation with a LD at 808 nm, we have detected ten fluorescence bandsin the spectral range spanning from visible to infrared. In visible region 4 upconversion bands have been observedcentered at 475, 547, 660, and 701 nm. Discussions of the energy transfer processes suggest that cross relaxations andexcited absorptions with the involvement of Tm3＋ 3F4, 3H5 and Ho3＋ 7I5 states are responsible for the four upconversionemissions. Comprsing the relative integrated intersities of 2μm (Ho3＋: 5I7 →5Is) and 1.8μm (Tmn3＋: 3F4 →3H6) bandswe have observed an efficient energy transfer from Tm3＋ (3F4) to Ho3＋ (5I7). Examination of the ratios of the intensityof 2μm band to that of 1.8μm band as a function of the ratios of Tm3＋ concentration (crm) to Ho3＋ concentration (cHo)indicates that small concentration ratios (cTm/cHo) lead to high efficient energy transfers of Tm3＋ (3F4) →Ho3＋ (5I7).