Solid-state Si-29 and Ga-71 NMR was used to study the synthetic gallosilicate Na16Ga16Si24O80 16H(2)O (Ga-natrolite). It has been shown that Ga-natrolite contains mainly Si(GaO4)(3)(SiO4) and Si(GaO4)(2)(SiO4)(2)-structural units and has sufficiently ordered structure. Temperature dependence of the spin-lattice relaxation time T-1 of Ga-71 nuclei has also been studied using solid-state NMR. Spin-lattice relaxation of the Ga-71 was determined to be governed by the electric quadrupole interaction with the crystal electric field gradients modulated by translational motion of H2O molecules in the Ga-natrolite pores.