The utility model provides an aluminum alkyl measurement preparing device. The aluminum alkyl measurement preparing device comprises a measurement tank, a liquidometer and a processing tank, wherein the upper portion of the measurement tank is provided with an air inlet hole and an air outlet hole, a feeding port is formed in one side of the measurement tank, and a discharging port is formed in the bottom of the measurement tank; the liquidometer is parallel with the measurement tank and communicated with the upper portion and lower portion of the measurement tank, the processing tank is connected with the measurement tank, a processing tank inlet is formed in one side of the processing tank, and the processing tank inlet is connected with the discharging port. The aluminum alkyl measurement preparing device can improve the preparing accuracy of aluminum alkyl, oxygen is isolated in the whole preparing process, other impurities are prevented from being led in, and the safety in the preparing process is largely improved.