The invention discloses an insulation structure suitable for a dry-type transformer with the voltage grade of 35 kV or above. A first cylindrical insulation device is arranged between a low-voltage winding and a high-voltage winding of the dry-type transformer, and a second annular cake-shaped second insulation device is also arranged at the end of the high-voltage winding. Shielding layers are arranged on the portions, close to the inner wall and the outer wall, of the first insulation device respectively, and the shielding layers are connected with the middle of the low-voltage winding and the middle of the high-voltage winding respectively to form equipotential. Shielding layers are arranged on the portions, close to the upper wall and the lower wall, of the second insulation device respectively, and the shielding layers are connected with the high-voltage winding and an iron yoke of an iron core respectively to form equipotential. Therefore, the second insulation device becomes a main bearing unit of the voltage at the end of the high-voltage winding. The insulation structure solves the problems that according to the structure of a high-voltage dry-type transformer, the main air channel distance is large, insulation is not reliable due to the fact that air serves as a main insulation medium, and cracking is likely to occur because the thickness of a resin layer of a windingis too large, and has the advantages of being good in practicability and reliability and capable of reducing the cost.