The invention relates to an acyl chloride vacuum rectification wastewater reclamation device and method and belongs to the technical field of wastewater reclamation. The device comprises a rectification device and a vacuum machine set, wherein a vacuum buffer tank is connected between the rectification device and the vacuum machine set; the vacuum machine set comprises a roots pump, a water injection device and an alkali liquor injection device. The water injection device is added into a traditional acyl chloride vacuum machine set, so that the problem that thionyl chloride enters the machineset to generate sodium chloride and sodium sulfite mixed salt with alkali liquor is well solved, and high salinity wastewater generation is avoided; meanwhile, cost is reduced, and the method has theadvantages of convenience, simpleness, easiness and practicability.