The objective of this research was to find out the interaction pattern in English for Foreign Language (EFL) classroom as well as to find out the percentage of each interaction pattern using Flanders Interaction Analysis Category System (FIACS). The researcher used descriptive qualitative as the research method. The subject in this research was 4th semester students. The data was collected through observation that was assisted by video recording and interview. The observation was done in five time meetings. Meanwhile the interview was done to the teacher and some students who had active and passive participation during the class. The major findings of this research are 1) the researcher found that teacher talk has 67,31%, student talk has 25,53%, and silence has 7,16%. 2) the predominant factors in EFL classroom from the most until the less frequent were; content cross, student participation, teacher support, and teacher control.