The paper presents results of the research on the power transmission from the tractor wheel onto the grounds with different properties. The research was carried out in field conditions with the use of a stand aggregated with a farm tractor. Firstly, an initial evaluation of tractive properties was carried out by determination of the traction force and efficiency. In the fundamental part of the research values of the useful power (drawbar power), power lost to the rolling resistance and the power lost to the wheel slip were determined. A vertical load of a wheel, except for the ground type, was an additional factor. Based on the obtained results, it was proved that a wheel used on soil had higher values of the traction force but lower tractive efficiency in comparison to the values obtained on sod. Analysis of the power transmission proved that these differences result from higher power losses related to the rolling resistance of a wheel used on soil. Moreover, it was proved that the increase of the vertical wheel load favours the improvement of traction properties (increase in the tractive efficiency and the drawbar power shares) only in case of a wheel exploited on sod.