There is a contradictive theory explored by the researchers about the use of first language in EFL classroom. One side believes that English is the only language should be used while another allows the practice of first language. Consequently, the presence of code-switching is still debatable. 
To cope with the above dilemma, this qualitative study aimed to describe the types, roles, and reasons of code-switching in PMDK classroom of SMAN 2 Mejayan during the implementation of Curriculum 2013. Purposive sampling was used to select the English teacher as the subject. Classroom observations were utilized to collect the data. Teacher’s interview, students’ focus group discussions, and researcher’s field notes were used to triangulate them. Then, they were analyzed through organizing and familiarizing, coding and reducing, and interpreting and representing. 
The findings revealed: first, there are three types of code switching used: tag-switching, inter-sentential switching, and intra-sentential switching, second, there are five roles of code switching implemented: to translate unknown vocabulary, to manage classroom, to explain grammar, to help students understand the material, and to index stance of empathy or solidarity, third, there are four reasons triggered code-switching: the students’ English proficiency, the distance between first and target language, the pedagogical material, and the lesson contents and objectives. It is concluded that code-switching brings the positive impact to the implementation of Curriculum 2013. Therefore, the students’ comprehension is augmented and the curriculum objective is achieved. Based on this fact, this study upholds the second theory to permit the practice of first language in EFL classroom. However, the use of English should not be avoided. 
Keywords: Curriculum 2013, code-switching, EFL classroom, English teacher