With the development of social economy, urban expressway traffic is in a state of normalized congestion. Therefore, it is urgent to carry out the research on the comprehensive improvement of traffic. Taking an expressway in the inner ring of Suzhou as an example, the causes of traffic congestion are studied and judged according to the multi-source data. The optimization strategy of highland linkage is used to formulate an improvement implementation scheme of traffic based on the concept of global optimal and systematical coordination. According to the analysis on the traceability of traffic flow, the possible diversion channels are sought. On the one hand, the engineering measures are used to improve the traffic capacity of diversion channels. On the other hand, the traffic management scheme of expressways is used to pilot the short-distance traffic on expressways into the diversion channels, which balances the flow of expressways and diversion channels so as to effectively alleviate the traffic congestion on expressways.