In recent years, the research on the combination of linguistics and translatology is becoming more and more abundant. This study not only introduces the study of the two subjects, but also explores the problems of gaps in translation process of ancient Chinese poetry. Through the approach of contrastive research, this study analyses the contrast of lexeme and semantic gaps reflected by nouns in ten English versions of Li Bai’s poem: Seeing Meng Haoran off at Yellow Crane Tower. Results show that the social and cultural factors behind the naming of nouns are closely related to the emergence of these gaps. Translators should find out exact causes behind those gaps and choose appropriate translation strategies according to the different types of the gaps.