Improving the material of axles is not only used to enhance the reliability of the use of railway wagon axle, but also an effective means to raise railway transportation capacity. The axle steel heat‐treated by “double normalizing and tempering” is applied as a sample in the current research. Not only the influence of V micro‐alloying elements on the microstructure of the sample is studied, their existing morphology, quantity and distribution feature, as well as changes of the mechanical properties are also analyzed. The analysis shows that the main strengthening mechanisms of the V micro‐alloying axle steel is the fine grain strengthening and dispersion strengthening, the grain refinement can improve the strength while improving the toughness, it is the most important way of strengthening and toughening.