The invention relates to a method for preparing an insulating heat conducting ceramic coating, which is prepared from one or more of polymer precursors such as polysilazane, polysiloxane and polycarbosilane serving as a base material, and multiple kinds of ceramic packing and active fillers as well as solvent and various auxiliary agents, and is prepared by the following steps of: 1, adding a certain amount of fillers, solvent and auxiliary agents into a polymer precursor, stirring the mixture evenly, and preparing the mixture into slurry after high-speed grinding; 2, coating the slurry on thesurface of a treated substrate material (comprising metal, ceramic, graphite, a C / C composite material and the like) in a brush coating or spray coating mode; 3, performing vacuum heat treatment on the substrate material with a coating at a temperature of between 100 and 300 DEG C for 1 to 2 hours to ensure that the polymer precursor performs a cross-linking reaction; and 4, performing high-temperature treatment on the treated material under the protection of a gas, namely treating the material at a temperature of between 400 and 1,000 DEG C for 1 to 5 hours, and then naturally cooling to obtain a ceramic coating on the surface of the substrate material. The insulating heat conducting ceramic coating has the characteristics of simple coating and heat treatment technology, excellent insulating property and heat conductivity, good high temperature resistance, excellent high-temperature cracking resistance and the like. The method can be widely applied in electronic and electrical industry.