Based on the improvement of genetic algorithm, this paper designs a method for detecting abnormal data in network transmission. Firstly, establish a network transmission abnormal data detection framework based on improved genetic algorithm, analyze the characteristics of network transmission data, then design the network host transmission communication mode, determine the communication direction of one-way flow and two-way flow, and finally design the network transmission abnormality based on improved genetic algorithm The data detection process obtains the update process of the abnormal data detection model. The experimental results show that, compared with the two traditional methods, the nonlinear data classification of the design method is more obvious and disjoint, the nonlinear data classification effect is better, and the recall and precision rates are higher than the common detection methods.