The invention discloses a material used for preparing gradient ceramic through the 3D printing technology and a preparation method of the gradient ceramic. The material comprises ceramic powder, a photoinitiator, prepolymer and a dispersing agent, wherein the mass percentage of the ceramic powder in the system changes in a gradient manner and sequentially increases or decreases, and the mass percentage sum of the components is 100%. The preparation method using the material to prepare the gradient ceramic includes the steps of firstly, preparing slurry, to be more specific, evenly mixing the prepolymer, the ceramic powder, the photoinitiator and the dispersing agent to obtain the series slurry with the mass percentage of the ceramic powder changing in a gradient manner; secondly, forming, to be more specific, coating the series slurry layer by layer, performing photocuring, and accumulating to obtain a green body; thirdly, performing post-processing, to be more specific, subjecting the green body to degreasing and sintering to obtain the gradient ceramic. The material is high in utilization rate and low in energy consumption. The preparation method can prepare gradient materials of optional complex shapes and can avoid subsequent processing.