The invention discloses a hollow-structured gallate luminescent material and a preparation method thereof, belonging to the field of luminescent materials. The general chemical formula of the luminescent material is (Ln1-xEux)3GaO6, wherein Ln is Gd or Y, and x is more than 0 and no more than 0.3. According to the hollow-structured gallate luminescent material, dispersed carbon spheres C are used as a template, and the prepared gallate luminescent material is of a spherical hollow structure, has controllable morphology, can effectively reduce the usage amount of rare earth metals, lowers down product cost and enables valuable rare earth resources to be considerably saved.