It has been merely 25 years since the Korean language began to be taught in contemporary Mongolia, but many studies have been made on Korean language education. As the goals of Korean language education in Mongolia has been changed to the training of Korean interpreters and translators, however, each school is executing translation education, but few studies have been made on translation education for Mongolian learners. What is more, because the methods of teaching and learning in the translation class are not efficient, many of learners who have completed such a course fail to be a professional interpreter or translator. Vast knowledge of vocabulary and grammar does not guarantee a learner to be a good translator. As it is essential for a translator to have grammatical abilities to understand the contents of a text to be translated and translate them correctly, grammar education is important as that much in the translation class. Thus, this study purposed to analyze grammatical errors observed commonly in Mongolian learners’ Mongolian-Korean translation and to find strategies to teach grammar in the translation class. For these purposes, this study analyzed the types and causes of grammatical errors made by Mongolian learners in the process of Mongolian-Korean translation using translation materials produced by 24 learners who were juniors at the Mongolian University of Science and Technology, and proposed teaching-learning methods for correcting grammatical errors efficiently in the translation class. In consideration of the nature of the school, scientific and technological contents familiar to the learners were chosen as analysis materials, and the causes of errors were classified into those from pronunciation, those from contrastive grammar, and those from the learner’s negligence, and grammar teaching-learning methods were suggested to correct such errors. As this study analyzed only 24 learners, who hardly represent all the Korean learners in Mongolia and whose level was not diverse, the findings of this study may not explain fully the current state of Korean translation education. Nevertheless, this study is expected to contribute to the activation of future research on Mongolian-Korean translation in various levels of translation process.