AbstractCode mixing is a language phenomenon in sociolinguistic study. Actually, code mixing often occursin a variety of phenomena in the society, including in the variety of public space media. Thephenomenon of code mixing in the public space medias is often seen, especially in heterogeneouscommunities of ethnics, cultures, and languages, such as in Lampung Timur area. The objective ofthis research is to reveal the interference of code mixing on the public medias in Lampung TimurRegency. This research is conducted by using observation method and image documentation. Dataare analyzed by using Huberman's content analysis and reduction techniques. Then, the analyzeddata are explained through Hoffman's theoritical approach on the occurrence of mixed-codephenomenon. The results reveal that there is an existence of code mixing phenomenon in publicspace medias. Code mixing can occur because of some factors namely, the first, there is a crossingbetween the language and culture of the people of Lampung (transmigration effects); secondly,code mixing occurs between Indonesian, English and local languages; and third, code mixingoccurs at word, phrase, and sentence levels. The result of this study is expected to be a referenceof science development and language policy. AbstrakCampur kode adalah gejala kebahasaan dalam ilmu sosiolinguistik. Ternyata, campur kode seringdilakukan masyarakat dalam berbagai ragam, termasuk ragam media ruang publik. Fenomenacampur kode di media ruang publik akan sering terlihat, terlebih pada masyarakat di wilayahheterogen dari sisi etnik, budaya, dan bahasa, seperti di wilayah Lampung Timur. Penelitian inibertujuan untuk mengungkap terjadinya campur kode dalam ranah media publik di KabupatenLampung Timur. Penelitian ini dilakukan dengan menggunakan metode observasi dandokumentasi gambar. Data dianalisis dengan menggunakan teknik analisis isi dan reduksiHuberman. Kemudian, data yang dianalisis dijelaskan melalui pendekatan teori Hoffman tentangterjadinya gejala campur kode. Hasil penelitian mengungkapkan adanya fenomena campur kodedi media ruang publik. Campur kode dapat terjadi karena pertama, adanya silang bahasa danbudaya masyarakat Lampung (pengaruh transmigrasi di Lampung), kedua, campur kode terjadiantara bahasa Indonesia, daerah, dan bahasa Inggris, dan ketiga, campur kode terjadi padatingkat kata, frasa, dan kalimat. Hasil penelitian ini diharapkan dapat menjadi bahan rujukanpengembangan ilmu pengetahuan dan penyusunan kebijakan kebahasaan.