In this article there was researched the budget classification reform process in the Republic of Moldova, considering it an important tool in the development and execution of the budget, as well as in the accounts of public institutions. It is investigated the unification process of the four accounts in one single integrated, which corresponds to European standards and modern financial reporting. Budget classification changes are researched and especially in the economic classification of budget spending, which unifies codes with unique integrated plan accounts. We present a study of transition from economic classification of expenditures from the old system to the economic classification of expenditures in the new system.