New measuring methods of the wheelset angle of attack of railway vehicles on board and on the ground have been developed by RTRI in Japan. Using these methods, wheelset angle of attack has been measured on curves in the field running tests of limited express trains on a narrow gauge commercial line. The results measured are as follows : (1) The measuring accuracy of these methods attains to that which we aimed. (2) The higher the velocity and the larger the curve radius, the smaller will be the steady angle of attack. The steady angle of attack of the first wheel is 0.28 degrees, and that of the second wheel is 0.02 degrees for a curve radius of 400 m at a velocity of 110km/h. (3) The measurements and the simulation results for wheelset angle of attack are close.