The utility model provides a device for insulating thermal treatment of high -voltage testing transformer, relates to the transformer field. Domestic and international inspection aassessment means totransformer insulation ageing have much at present, nevertheless never have fine insulating thermal treatment means afterwards. The utility model discloses a transformer thermal treatment jar, vacuumsensor, capacitance changer, temperature transmitter, vacuum pump, heating device and the controlling means who links to each other with vacuum sensor, capacitance changer, temperature transmitter, heating device, electric capacity information that the capacitance changer was gathered including just between the winding layer at heat treatment process's transformer, capacitance between winding andground connection thermal treatment jar, controlling means according to the electric capacity information who gathers control heating device, heat treatment process is controlled with the ration to vacuum pump work. This technical scheme can conveniently realize insulating qualitative effect analysis and the quantitative analysis who handles, realizes controllable insulating processing procedure,stops the insulating nondeterminacy who handles of transformer for the high -voltage testing.