The goal of this study is to find out how the students and parents perceive Co-teaching English class and what difficulties the students have in English class taught in English with a native English teacher and to give some suggestions to overcome these difficulties. This study has proposed three research questions, the first question is "What kind of language skill is mostly improved from Co-teaching?" The language skill that is mostly improved from Co-teaching is the speaking skill particularly "pronunciation". The students have a chance to be able to listen to an authentic pronunciation of English, and to improve their speaking skills by practicing and being corrected instantly by their native English teacher. The natural interaction between the students and native English teachers is a vital way to gain confidence to speak English and to have less fear towards foreigners. The next question is "What are some difficulties encountered by the students? The mostly mentioned difficulties that the students encountered are "hard to understand, use of difficult vocabulary/difficulty in communication, speak too fast and not enough explanation, doesn't have enough time, not organized and can't concentrate well and no Korean at all". The third question is "What are the parent's perception about Co-teaching?" The parents support their children's confidence in speaking English. They want their children to have more time and interaction with the native teacher and eventually gain speaking confidence and correct pronunciation. This maybe the reason why most of the parents send their children to private English institutions. Although at school their children have native English teacher in their English classes, the parents' perception is lack of chance for their children to personally interact with their native English teacher due to a large number of classroom size. The difficulties that students encountered and parents difficulty perceptions can be divided into three main areas: teacher-related factors, language learning content factors and other factors. The suggestions on how to deal with these difficulties are offered for teacher's inspiration.