The invention relates to the technical field of medical instruments, in particular to an aspirator for preventing aspiration operation. The invention relates to a surgical aspirator, and aims to solve the problems that the conventional surgical aspirator can adsorb intestinal and abdominal tissues of a patient, needs to repeatedly suck liquid, is low in liquid suction efficiency, easily infects wounds of the patient and can cause backflow. According to the technical scheme, the operation aspirator capable of preventing aspiration by mistake comprises a protective shell, a circular truncated cone communicating vessel and the like; a circular truncated cone communicator is installed on the lower portion of the inner side of the protective shell. According to the device, during an operation, when hydrops in the intestines and the abdominal cavity of a patient are sucked, the liquid suction device does not need to be taken out and put in multiple times, so that the liquid suction operation is more convenient, meanwhile, in the liquid suction process, the situation that tissues in the intestines and the abdominal cavity of the patient are sucked mistakenly, and the patient is injured is prevented, the liquid suction continuity and efficiency are effectively improved, and the operation efficiency is improved. Meanwhile, accumulated liquid is prevented from flowing back or blocking in the liquid suction pipe is prevented, and the liquid suction stability is effectively improved.