In the field of communication, the importance of the concept of langue, which was brought into attention by Saussure's seminal work on language, cannot be too much exaggerated,. But Saussure did not give a clear definition of langue. Based on my reading of Saussure, Ⅰ find that the concept 'langue' has two meanings. "Langue' may be seen as a 'system', in which its components, signs, are interdependent of each other. 'Langue' also refers to the rules governing language, such as the rule of combination. To sum up, langue is a network in which signs are linked to each other in various forms such as association, differentiation and combination.