Double trailer combination is an efficient transportation model that is currently widely used in Europe, America, Australia, and other places. In recent years, China has been conducting research on the application technology of dual trailer trains in order to promote energy conservation and emission reduction in the road transportation industry, and achieve the goal of carbon neutrality and peak carbon emissions. According to the display requirements of Chinese road transportation enterprises, a B-double has been developed, which can transport two 20 foot standard containers. In order to ensure the transportation safety of the vehicle, testing and evaluation of key performance such as road passing ability, roll stability, driving stability, and braking safety will be carried out. By comparing the performance research of tractor and semi-trailer in China, evaluate the operational safety of B-double. The research results indicate that the passing ability of double trailer combinations is slightly higher than that of tractor and semi-trailer, and the lateral stability, handling stability, and braking safety can meet the requirements of current standards.