The aim of this study is to identify endogenous factors that determine the level of investment in farms of economic size over 16 ESU in selected CEE countries belonging to the European Union. The empirical material were data from Farm Accountancy Data Network FADN for the years 2004-2009. Analysis of endogenous factors determining investment activity farms showed that the positive effect depends on the level of executed investment economic situation of agricultural holdings, especially the level of generated net farm income and profitability of agricultural production and the level of farm support under the agricultural policy of the European Union.