Translation is considered as an essential skill in foreign language learning. Especially, it plays an important role in Spanish teaching in Taiwan. This research aims to study interlinguistic transferences problems, which are observed from translation exercises from Chinese to Spanish written by Taiwanese students. About interlinguistic transferences problems, we focus on the interference of their mother tongue: omission of conjunction on adverbial subordinate sentences. Using Contrastive Analysis we try to explain the reasons of the interference appeared in Taiwanese students' Spanish learning.