Penelitian ini bertujuan untuk mengetahui strategi komunikasi apa yang sering muncul selama proses pembelajaran di kelas ESP, menemukan code switch yang terjadi selama proses presentasi, dan mengetahui maksud dari code switch yang digunakan oleh mahasiswa. Penelitian ini adalah non experimental descriptive study. Sample dari penelitian ini ada 20 mahasiswa baru dari kelas A program studi pendidikan matematika di Universitas Lampung. Hasil dari penilitian ini menunjukan bahwa dari 12 CSs, mahasiswa menggunakan 9 CSs. Kemudian strategi komunikasi yang sering digunakan oleh mahasiswa adalah code switching (36,28%), appeal for help (16,03%), and time gaining strategy (30,37). Di sisi lain, terdapat 3 jenis code switching; inter-sentential switching (51,16), intra-sentential switching(41,86), and, tag switching (6,98). Terlebih lagi, berdasarkan hasil dari code switching, hal itu dapat disimpulkan bahwa code switching disebabkan oleh 4 faktor; mereka adalah kata, frase, penghindaran kesalahpahaman, dan kemudahan berkomunikasi. The research aimed to find out what communication strategies were mostly appeared during the learning process at ESP class, to find out the code switch occurred during the presentation and also the meaning of the code switch that the students used. This research was non experimental descriptive study. Samples in this study were 20 fresh college learners of mathematic study program in A class at University of Lampung. The results show that, of the 12 CSs available, the students used 9 CSs. Then, the CSs that were most frequently used by students were code switching (36,28%), appeal for help (16,03%), and time gaining strategy (30,37). On the other hand, there were 3 types of code switching; inter-sentential switching (51,16), intra-sentential switching(41,86), and, tag switching (6,98). Moreover, based on the result of code switching, it could be concluded that code switching was caused by 4 factors; they are word, phrase, avoidance of misunderstanding, and easier communication.Keywords. Communication Strategies, Code Switching, ESP Class
