Network traffic classification aims at identifying the application types of network packets.It is important for Internet service providers(ISPs)to manage bandwidth resources and ensure the quality of service for different network applications.However,most classification techniques using machine learning only focus on high flow accuracy and ignore byte accuracy.The classifier would obtain low classification performance for elephant flows as the imbalance between elephant flows and mice flows on Internet.The elephant flows,however,consume much more bandwidth than mice flows.When the classifier is deployed for traffic policing,the network management system cannot penalize elephant flows and avoid network congestion effectively.This article explores the factors related to low byte accuracy,and secondly,it presents a new traffic classification method to improve byte accuracy at the aid of data cleaning.Experiments are carried out on three groups of real-world traffic datasets,and the method is compared with existing work on the performance of improving byte accuracy.Experiment shows that byte accuracy increased by about 22.31%on average.The method outperforms the existing one in most cases. Network traffic classification aims at identifying the application types of network packets. It is important for Internet service providers (ISPs) to manage bandwidth resources and ensure the quality of service for different network applications. However, most classification techniques using machine learning only focus on high flow accuracy and ignore byte accuracy. classifier would obtain low classification performance for elephant flows as the imbalance between elephant flows and mice flows on Internet. elephant flows, however, consuming much more bandwidth than mice flows.When the classifier is deployed for traffic policing, the network management system can not penalize elephant flows and avoid network congestion effectively. This article explores the factors related to low byte accuracy, and secondly, it presents a new traffic classification method to improve byte accuracy at the aid of data cleaning. Experiments are carried out on three groups of real-world traffic datasets, and the method is compared with existing work on the performance of improving byte accuracy. Experiment shows that byte accuracy increased by about 22.31% on average. method outperforms the existing one in most cases.