The resistor device is provided with a resistive plate (11) of metal plate material, which is used as a resistance body; a radiative plate (15) of metal plate material, which is spaced from the resistive plate and intercrossed on the resistive plate; a molded resin body (19), which encloses an intercrossing portion of the resistive plate and the radiative plate; terminal portions of the resistive plate (11a), which comprises so that both ends of the resistive plate extending from the molded resin body are bent along an end face and a bottom face of the molded resin body; and terminal portions of the radiative plate (15a), which comprises so that both ends of the radiative plate extending from the molded resin body are bent along an end face and a bottom face of the molded resin body. Accordingly, the surface-mountable resin-sealed metal plate resistor device is enabled to increase the power capacity drastically and to improve the reliability without changing most of the size.