A vehicle, a single-wheelset/double-wheelset trackless train and a tracking and steering control method therefor are provided in the invention. The method includes the following steps. During traveling of the vehicle, steering information of the vehicle is continually collected by the controller. Information about a guiding front wheel turning angle, a controlled rear wheel turning angle, a vehicle body position angle, an included angle between vehicle bodies, and a vehicle travel time and speed is collected; an interval for data collection is determined according to a distance between a guiding front wheel and a controlled rear wheel; and when the controlled rear wheel travels to a certain point near a front wheel travel track, the controlled rear wheel is controlled to travel in a travel direction same as that when the front wheel travels to the point. According to the rear wheel tracking and steering control method, the objective that a controlled rear wheel operates in a manner of highly approaching a guiding front wheel track can be achieved; and the higher a data collection frequency is, the higher a track fitting degree of the front wheel and the rear wheel is.