The main purpose of the study was to assess changes in labour profitability against changes in the level of investment outlays in Poland in a regional approach. Empirical material consists of statistical data from the Central Statistical Office for the years 2000-2017. The following diagnostic variables were used for the analysis: (1) characterizing the profitability of the labour factor – gross value added in agriculture per one agricultural employee; (2) characterizing the investment activity of farmers – the value of investment outlays in agriculture per one employee in agriculture, the value of investment outlays in agriculture per 1 ha of agricultural land, the value of investment outlays in agriculture in relation to the value of gross fixed assets in agriculture, the value of investment outlays in agriculture in relation to gross value added in agriculture. On the basis of a set of diagnostic features describing the investment activity of farmers, a classification of voivodships was carried out using cluster analysis using Ward’s method, and a statistical evaluation of the relationship between the investment activity of farmers and the profitability of labour was performed. There has been a significant diversification of farmers’ investment activity and labour profitability in terms of regions. It was found that the level of investment outlays is a crucial factor in the process of improving the efficiency of the use of the labour factor. A level of investments that is loo low does not allow for favourable structural changes and for modernization and restructuring of agriculture to take place.