According to the recommendations of the OECD, potential budget income, whose collection was relinquished by means of applying special tax solutions, has to be treated as subventions, which should be included in calculation of the PSE factor, monitoring the support for agriculture. However, in practice a number of countries, due to various reasons (both political and technical), do not treat the 'tax' support for agriculture as an alternative manner of support for direct budget expenditure; therefore, the level of public subsidy for agriculture is usually understated. The article presents forms of support for the agriculture which are less clear and even hidden in special tax structures; despite the fact that these forms provide measurable profits, they are usually not treated as an element of subsidy in Poland. The authoress makes an attempt at defining the off-budget support for the agriculture by the tax system, often called tax expenditures of agriculture and shows potential profits and losses resulting from application of special structures in the taxation of agriculture. Disclosing tax expenditures, in the budget, witch may be considered, a substitute for the state's expenditures, should contribute to making efficient public decisions, especially with respect to the agriculture. This will allow for certain transparency of policy pursued with respect to agriculture and a clear division between the state's expenditure policy and income policy. Lack of any estimates with respect to tax expenditure of agriculture means that information with respect to the total state budget's expenditure on agriculture is not complete and the actual support for agriculture in usually greater.