In this paper, I want to point out that competitive advantage cannot be understood only through the understanding of the company as a whole. The competitive advantage stems from the numerous activities the company carries out in supporting its product, in marketing, shipping and manufacturing. The principle of a modern business strategy is to maintain a competitive advantage. To identify competitive advantage, it is necessary to define the value chain of a company to compete in a particular industry. The competitiveness range has a strong influence on competitive advantage as it can shape the economy and value chain settings. A broad range will allow the company to carry out its activities internally, while a narrow range will allow the value chain to be adjusted to ensure that the individual target segment achieves lower costs. The value chain is a series of activities that shows how a product progresses from raw material to end users. It breaks down the company into strategic activities to better understanding cost trends and the potential source of differentiation. The value chain consists of value activity and margin, and displays the total value. To perform their function, value activities use human resources, purchased inputs and some form of technology. Value activities are divided into primary and support activities, they are elements of competitive advantage building and are connected by links within the value chain. And links are the relationship to which one activity is performed and the cost of performing another value activity. The value chain is a basic tool that recognizes competitive advantage, therefore, it finds ways to maintain that advantage, and also plays a maintenance role in designing the organizational structure. The customers also have value chain. The differentiation of a company comes from the way it describes how the value chain is linked to the customer value chain.