In order to solve problem of high miss detection rate and false detection rate in current methods of eliminating abnormal big data in network, a method under asynchronous transmission based on ant colony-genetic algorithm is proposed. Data is validated by measuring proximity and initialization parameters of ant colony are set and real-time evolution rate of offspring is counted in which pheromones are used to train ants, then chromosomes are coded to obtain fitness function of particles. The fitness function is used to calculate individual optimal value and global optimal value of particles. Then concentration of global pheromone is used to judge whether the Ant Optimization meets end condition. If it is, large uncertain data are detected and eliminated. Experiments show that the average missed detection rate is about 2.5%, and the false detection rate is low.