Motivation is one of important aspects which students need in learning English. Although motivation is important in learning English, some students at a Private Senior High School tend to be demotivated when learning English. This research aimed to find out students’ demotivating factors when learning English and the strategies used by students to cope with the demotivating factors. The researcher selected three of the second year students at a Private Senior High School in Yogyakarta. The researcher asked some recommendation from the teacher to get students showing negative behaviour as the participants. The researcher collected the data through interview. Then, the researcher used descriptive qualitative to explain the data. The first finding of this research showed that there were four factors which made the students feel demotivated in learning English. Those were difficulties in grammar, limited vocabulary, and unsupportive classmates. Also, there were two categories found in unsupportive classmates such as competing and bad attitude of classmates. The researcher also found the strategies used by students to cope with the demotivating factors. Those strategies were learning grammar, taking nots of some vocabularies, joining a private class with tutors, and discussing feelings with classmates. There were five categories in vocabulary problems namely taking notes of some vocabularies, finding vocabulary meaning, memorizing vocabulary, underlining vocabulary meaning of vocabulary, and listening to the music.