The purpose of the work was the evaluation of changes in the effectiveness of the use of labor in agriculture against a background of changes in the relation of production factors. The analysis is presented on a regional basis. The empirical material consisted of CSO statistical data from 2000-2016. The following diagnostic variables were used for analysis: (1) the value of gross agricultural output per one employed in agriculture, (2) technical work equipment – the gross value of fixed assets in agriculture per one employed in agriculture, (3) the number of people working in agriculture per 100 hectares of agricultural land (AL), (4) technical equipment of agricultural land – the gross value of fixed assets in agriculture per 1 hectare of AL. Based on a set of diagnostic features describing individual voivodships in Poland, their classification was performed using the cluster analysis of the Ward method. A decrease in the technical equipment of labor was recorded, and an increase in the technical equipment of agricultural land and the number of people working in agriculture per 100 hectares of AL. At the same time, these changes varied in individual groups of voivodships. Analysis of regional differentiation demonstrates that, in voivodships with much more favorable relations of production, labour efficiency was higher. In addition, in these voivodships, the average annual rate of changes in labor efficiency was also at a higher level. This may result in a growing disparity in the level of farming efficiency.