The invention relates to a vehicle urea machine. The vehicle urea machine comprises a stirring device, wherein the stirring device comprises a stirring pot (1) and a driving mechanism (2), the stirring pot (1) is of a closed structure, and is used for containing solute and a solvent for producing an urea solution, the driving mechanism (2) is used for driving the stirring pot (1) to do rotation movement to stir a mixed solution formed by the solute and the solvent in the stirring pot (1). According to the vehicle urea machine provided by the invention, the stirring device comprises the stirring pot and the driving mechanism, the driving mechanism is used for driving the stirring pot to rotate, the solute and the solvent in the stirring pot can be fully mixed during the rotation process, and since the stirring pot is of the closed structure, impurities are prevented from being introduced to affect the quality of the mixed solution; the stirring device is simple in structure, the stirring process is easy to control and the operation is convenient.