Language meaning not only comes from vocabulary and grammar,it also dependson specific context.Context is the basis of language and an essential factor ofdetermining language meaning.Context is indispensable in explaining utterancemeaning,especially cognitive context.On the basis of achievements of predecessors　　 research,this paper starts from the close relationship between cognitive context andutterance understanding,and deeply explores the role of cognitive context in utteranceunderstanding further,with the aim of providing some reference for communicators tounderstand utterance correctly in communication process.　　 The traditional context view regards context as an all-embracing concept,includingthe specific context in verbal communication,and the cultural context of partiesinvolved.It is extensive and objective.While the cognitive context holds that context isthe result of the internalization,cognition and conceptualization of pragmatic factors.　　 The basis of language communication is the shared cognitive environment.Languagecommunication is cognitive activity according to certain inferential rules.Althoughcognitive context has a lot in common with traditional context in the description ofcontextual elements,the organism of the two differs a lot.Cognitive context makesbrand new explanation of context from the perspective of human cognitive sciencewhich introduces new ideas to the study of context.As an important notion in relevancetheory,cognitive context has direct relation with relevance of utterance and contextualeffect.Sperber and Wilson put forward their ideas of utterance understanding which isbased on relevance theory.They think that utterance understanding is a process ofsearching for optimal relevance in certain cognitive context and achieve contextualeffect.