This research aims to understand the factors affecting high achievers‟ speaking performance. This research is descriptive qualitative research. Research methods for this research are using documents to gather the information about the students‟ score and semi-structured interview to collect the information regarding the factors affecting their speaking performance. The samples are the students who got A score in Academic Speaking subject consist of 15 students with 2 men and 13 women and also the lecturer. The results of this research indicate factors like vocabulary, grammar, fluency, confidence, and motivation are important and affecting their speaking performance in class. Based on the interview with lecturer the important factors in speaking which affect students‟ score are pronunciation, vocabulary, grammar, seriousness, confidence and voice, while for interview with students all students agree with vocabulary, confidence and motivation being important factors in their speaking performance while for grammar most students think it is imporatant in speaking and the rest think it is not very important. These factors also depend on each other according to students‟ opinion in the interview.