The invention discloses a direct-current resistance potential transformer which comprises a hollow insulator, a shielding ring, an insulating separation plate, an inflation and deflation device and nresistance capacitance voltage dividing modules, wherein the shielding ring and the inflation and deflation device are respectively arranged at the two ends of the hollow insulator; the n resistance capacitance voltage dividing modules are sequentially connected in series and fixed in the hollow insulator; the insulating separation plate is arranged between the resistance capacitance voltage dividing modules and the inflation and deflation device; the hollow insulator is filled with an insulating medium; each resistance capacitance voltage dividing module comprises an insulating support pipe,a voltage dividing capacitor and a plurality of measuring resistors; the voltage dividing capacitors are fixed in the insulating support pipes; the measuring resistors are sequentially connected in series and fixed on outer walls of the insulating support pipes; the measuring resistors connected in series are connected in parallel with the voltage dividing capacitors; and the insulating support pipes are filled with insulating media. According to the direct-current resistance potential transformer, resistance capacitance voltage dividers in the potential transformer are modularized, and the modularized resistance capacitance voltage dividers in different quantity are connected in series, so that different voltage classes are realized; the expandability is high; and large-scale production is facilitated.