Absorption spectra, emission spectra induced by 346 nm, 363 nm (1D2), 475 nm(1G4), 698 nm (3F2, 3F3) and 801 nm (3H4) light, and excitation spectra of fluorescence spectral lines at wavelengths of 454 nm (1D2→3F4), 475 nm (1G4→3H6), 646 nm (1G4→3F4), 806 nm (3H4→3H6) of trivalent Tm3+ ion in YVO4 crystal were measured. Transition processes of the energy levels of Tm3+ are analyzed in details. The idea of energy transfer and new transition channels between Tm:YVO4 host and energy level of Tm3+ ions were proposed. It is confirmed that there are energy transfer processes including 1D2+3H6→1G4+3F4 and 1G4+3H6→3H4+3H5, cross relaxation process 1G4+3H6→3F2+3F4 may be present yet. These energy transfers make the upconversion 1D2→3H6 (454 nm) difficult while the upconversion luminescence of 475 nm (1G4→3H6H) is strong and 3F0 is the potential infrared laser emission energy level.