A double-insulated motor and pinion device including a motor, motor-fixing seat, pinion, pinion sleeve and double insulation sleeve. The motor and motor-fixing seat are connected together to form a motor assembly. The pinion is mounted on a motor shaft. The pinion sleeve is mounted under the pinion, and the double insulation sleeve is connected under the pinion sleeve. The pinion, pinion sleeve, and double insulation sleeve are mounted together to form a pinion assembly. The pinion assembly is mounted on the motor assembly. It can solve the requirement of basic insulation and reinforced insulation of a series of high voltage direct current products by adding two insulation parts, while reducing space and lowering cost.