The work aims to study the design and test verification of LNG railway tank car to provide reference for its application. Firstly, the technical parameters and structure composition of LNG railway tank car were introduced. The design, research and simulation analysis of the tank car structure were carried out by CAD and FEM technology, and the mechanical properties and vacuum insulation indexes of the tank car were verified by railway static strength and impact test, low temperature performance test, etc. With axle weight of 23 t and load not more than 41 t, the tank car could run safely at the maximum speed of 120 km/h, the static evaporation rate (liquid nitrogen) was 0.08%/d, and the maintenance time (liquid nitrogen) reached 92 days. The technical parameters and performance indexes of LNG railway tank car have reached the requirements of design documents and related standards.