Accounting systems of various entities operating in the Polish economy differ, although they are based on one act on accounting. These differences usually result from the specificity of their operating conditions. This study presents the accounting system in the Polish economy and the specificity of the budget accounting system. In addition, a comparison of the enterprises accounting system and the budget unit operating in the area of public finance was made, indicating similarities and differences. The accounting tasks specified in the balance sheet law were adopted as the basis for comparisons.