Finance and accounting are the most important sectors in each company. It is quite common in the literature to compare the importance of the financial aspect of business with the importance of each man's bone. Within this, one of the most important areas is certainly cost calculation, and given the new contemporary business conditions, cost accounting is getting more attention. Literature differentiates traditional and contemporary cost accounting methods, although the importance of switching to modern methods increasingly emphasizes, companies still uses some traditional cost accounting methods. One example of such companies is the company Invest Sedlić d.o.o from Bjelovar, which deals with the purchase of cereals and oil products on domestic and foreign markets and is redeemed from small, medium and large producers of agricultural crops. In accordance with the aforementioned, the topic of this paper is "Calculating the Cost of Production through the example of Invest Sedlić d.o.o", and the work includes the results of the primary and secondary research.