Abstract Na5Eu(MoO4)4 is a stoichiometrlc host luminescent material. The light emessioB comes from high concentration host ions Eu3+. In the present work, the effects of hydropressure on fluorescence of Eu3+ in Na5Eu(MoO4)4 are invistigated under 0-5.0 GPa using a diamon anvil high pressure microspectroscopic system. According to crystal field theory, the energy level fexpressinns of Eu3+ (in approximatry D2d symmetry site) are calculated and fit with the experimental data of energy levels, under high pressure, then the ratios of crystal parameter variation △Bkq (kq= 20,40 44, 60 and 64) with pressure variation △P are determind. A comparison of above results with that of YVO4:Eu3+, in which Eu3+ is an active impurity, is also made.