The invention belongs to the technical field of energy conservation and environmental protection, and particularly relates to a dangerous waste liquid incineration pretreatment system and a treatmentmethod. The system comprises a roller conveyor, a waste liquid barrel, a vacuum feeding tank, a waste liquid buffer tank, a pneumatic diaphragm pump, a cooler, a vacuum pump, a circulating water tank,a waste liquid tank and a waste liquid conveying pump, wherein a weighing device is arranged at the lower end of the vacuum feeding tank, when the system works, the vacuum pump is started, under a negative pressure environment, dangerous waste liquid in the waste liquid barrel is sucked into a vacuum feeding tank, then enters the waste liquid buffer tank, and finally is pumped into a waste liquidtank area through the pneumatic diaphragm pump, the waste liquid conveying pump conveys the waste liquid in the waste liquid tank to a sewage treatment station, and meanwhile, a gas outlet at the topof the circulating water tank, a gas outlet at the top of the waste liquid buffer tank and a gas outlet at the top of the waste liquid tank discharge generated waste gas into a deodorization or incineration system. The system simultaneously, efficiently and stably conveys a plurality of waste liquid barrels, and is safe and reliable in operation environment.