The invention discloses an extra-high voltage power transformer check vehicle, which comprises a cab and a carriage which is positioned on the rear part, wherein the rear part of the carriage is provided with a movable compartment; an accommodating space between the carriage and the compartment comprises an operation control chamber and a high-voltage chamber which are separated from each other through an instrument rack; a power transformer check instrument comprises a voltage transformer check instrument and a current transformer check instrument; the voltage transformer check instrument ismovably arranged in the high-voltage chamber; the current transformer check instrument is arranged on the instrument rack; the rear part of the movable compartment is provided with a rear vehicle door which can be turned towards rear lower space to be opened; the rear vehicle door is provided with a plurality of electric supporting legs; when the rear vehicle door is opened in a horizontal state,the electric supporting legs are supported below the rear vehicle door; and through the structural arrangement, the check vehicle can safely and efficiently realize check of a power transformer on site; and the check vehicle is suitable to be popularized and used in industry.