The topic of this paper is concerned in a possibility of connection of the microeconomics theory and the business economics theory. The goal of the submitted paper is an implementation of an economic efficiency as a microeconomic component to the business economics with a regard for an economic practice of companies in the Czech republic. I use an analogy of the microeconomics and the business economics concept of total revenues and total costs to this implementation. The main of the text is reserved to opportunity costs because it is fitting to total economic costs from a point of view of business economics theory and practice is complicated. On basis of accepted analogies I generalize conclusions about an economic efficiency and I think of a product possibility frontier in a company too.