A manufacturing method of a dielectric device includes steps described below. (1) Mixing step: Powders serving as a matrix and additive powders for sintering the matrix are mixed. (2) Mixture heat-treating step: The mixture of the matrix and the additive that has been subject to the mixing step is heat-treated. (3) Deposition layer formation step: The material powders obtained through the mixture heat-treating step are injected toward a substrate so as to form a deposition layer on the substrate. (4) Deposition layer heat-treating step: The deposition layer formed on the substrate through the deposition layer formation step is heat-treated so as to form the dielectric layer on the substrate.