English pronunciation is quite difficult for Indonesian students since they have been used to speaking their mother tongue since childhood.The purpose of this reseach are to explain the pronunication problem made by the fourth semester students English Education department at University of Walisongo Semarang, in terms of consonants, vowels and also explain the factors can affect the pronunciation problems. The method of research is qualitative using case study research design. The participant of this reseach were 37 students who are still in the fourth semester English Department Students by C class. The data were collected through recording test and interview. The methods of analyzing data were the techniques proposed by Miles and Huberman, namely data reduction, data display, and conclusion drawing. The result of research showed that the pronunciation problems are in segmental features included the problems with consonant sounds were (v), [ð], [θ], [t∫], (z), and deletion the sounds [k], [ɡ], [t], and [s] and the vowel sounds were [iː], [ɛ], [Λ], [ə] and [ɔ:]. The top theree pronunciation problems by consonant sounds: The sound [v]: 26.64%, the sound [θ]: 13.19%, the sound [t∫]: 11.11% and the top three pronunciation problem by vowel sounds: The sound [ə]: 24.37%, the sound [ɛ]: 17.65% and the sound [ɔ:]: 14.77%. There are four factors can affect pronunciation problem, those are: (1) mother tongue, (2)amount of exposure,(3) the age factor and (4) motivation and concern for good pronunciation.It is suggested for the next reseacher to investigate pronunciation problem related suprasegmental features and also it is suggested to investigate the treatments of pronunciation problem so that the students can minimize mispronunciation and the teacher should be introduce course to be trained on phontetics to help students improving their pronunciation