The invention discloses a preparation method of a H-grade water-solubility silicon steel sheet paint, which comprises the following steps of: taking raw materials such as 10-20 parts of plant oil, 5-10 parts of polyatomic alcohol, 5 parts of binary acid, 3 parts of trimellitic anhydride, 5 parts of cosolvent, 3 parts of neutralizer, 0.5 part of coupling agent, 30 parts of alcohol, 25 parts of nanometer inorganic packing, 0.15 part of pigment, 5 parts of melamine resin, 0.1 part of flatting agent, 2 parts of dispersing moistening agent, 0.1 part of deforming agent and 10 parts of water according to a weight ratio, and preparing an environmental-friendly product with good combination properties for large generators through the synthesis of alkyd resins, the coupling treatment of the nanometer inorganic packing, the mixing and dispersion of materials such as the inorganic substances and the like in a paint, the grinding of the paint vehicle and the like. The preparation method has the advantages of solving the problems of sedimentation, aggregation and blocking of powder in paint liquid under the condition of high content of inorganic powder, obviously increasing the storage stability of the paint liquid and the hardness of a paint film, effectively reducing the discharge of poisonous and harmful gases in the production process and reducing the harm to the health of human bodies.