Author study is conducted in the field of research on discourse markers that have attracted many scholars attention both at home and abroad in recent years. The authorfirst review the previous researches on discourse markers, particularly the four approaches: Coherence Approach, Grammatical-Pragmatic Approach, Relevance Approach, and Sociolinguistic Approach. Based on Frasers (1996, 1998) model and Liao Qiuzhongs(1986) model for analyzing discourse markers, I then describe the classification of discourse markers in both Chinese and English. Next Author discuss the functions of oh and its translation into Chinese. Eleven Chinese novels and nine English novels and movie scripts are examined. Relevance Theory provides us a new perspective to understand such functions served by oh as recognition marker, receipt marker, answer marker, emotion marker and repair marker.Besides Relevance Theory informs us that translation should be optimally relevant to target readers or audience without imposing unnecessary processing effort burden upon them. In analyzing the translation of oh as emotion marker into Chinese, I point out that its translation should not be the same always employing the Chinese expression , but has to be different in different contexts. And oh may not be translated at all in some circumstances.