To solve the problem of DBC (Database CAN) protocol data analysis and structure characterization in the CAN network, in this paper, the DBC file protocol is analyzed through regular expressions, and the CAN network protocol is characterized by using the multi-tree structure. To solve the protocol analysis problem in different formats of Intel and Motorola, an expression method of signal color blocks in the data field of messages and a start bit conversion formula are proposed. The CAN network data management software is designed and developed based on the C# language, and the CAN network protocol is output as a DBC data management file. An actual vehicle test is conducted, which verifies the validity of the DBC protocol analysis method proposed in this paper.