In Inner Mongolia, those Mongolian students face lots of difficulties in learning English. Especially the English translation ability of Mongolian students is a weak point. It is worth to think a problem that how to let our students use the English freely on a certain foundation. This article investigates the problems of Mongolian English learners by analyzing some errors in their English-Chinese translation in three ways. Such as their inflexible use of translation skills, mistakes in idiomatic usage, inflexible and boring statements and the lack of knowledge in cultural background. The paper also offers some solutions to the problems.