The invention relates to a novel electromagnetic current transformer device. The device comprises a straight column shell, wherein an upper opening is formed in the left side of the straight column shell, and a connecting plate is arranged at the opening through a connecting plate flange; a reducing fixed flange is connected at the left opening of the straight column shell through the left opening flange, and a conical shell with gradually reduced diameter is soldered at the opening on the right side of the straight column shell; a right external connecting flange is arranged at the opening at the right end of the conical shell; a supporting column is arranged inside the straight column shell; the opening at the left end of the supporting column is fixedly connected with the edge of the inner whole of the reducing fixed flange; an assembly flange is fixedly arranged outside the opening at the right end of the supporting column; and an equalizing ring is fixedly arranged on the assembly flange and positioned at the opening at the right end of the supporting column. The existing intermediate transition thick flange is reduced, and the equalizing ring is manufactured by bending an annular steel pipe, so that the cost for the novel electromagnetic current transformer device is reduced, the processing is easy, and the cost is low.