The organization of any expedition for the Imperial Academy of Science was a complex process from both a scientific and administrative point of view. Long-term expeditions demanded many months (sometimes several years) of preparatory work that included, among others issues, the obtaining of permit documents and the necessary funding. The expenses of the expedition of the Academy of Science included funds for travel, for salary, for food, to purchase the equipment and collections as well as for “unforeseen expenditures”. The government had a flexible approach to financing the expeditions and scientists could bring money (such as banknotes, silver ingot, silver rubles or gold doubloons) or get money from the Treasuries in the remote provinces. An analysis of the expeditions’ budget gives us the possibility to better understand scientists’ everyday life and work on the expedition and also in St. Petersburg during the preparatory stages. In my paper I’m going to demonstrate the main expense items for the “average” expedition in the first half of 19th century. The examples I will discuss include the budgets of well-known expeditions such as the ones made by K.M. von Baer (1837), A.F. Middendorf (1842-45) and some others.