A railway vehicle and an axle box structure thereof are provided. The axle box structure includes an axle box body and a positioning node mounting seat. The axle box body includes an upper box body and a lower box body. The upper box body and the lower box body enclose a bearing mounting chamber together. A lower end surface of the upper box body has a convex portion, and an upper end surface of the lower box body has a concave portion. A first semi-circular hole and a second semi-circular hole are respectively provided at the middle of the upper box body and the lower box body. If the convex portion and the concave portion are assembled in a sealed coupling manner, the bearing mounting chamber is formed by the first semi-circular hole and the second semi-circular hole.