Radio broadcasters, both government radio broadcasters, in this case Radio Republik Indonesia (RRI) broadcasters and private radio broadcasters have an important role in delivering news or conversations to their listeners. For this reason, broadcasters should be able to apply the use of the Indonesian language properly and correctly both in the context of official and unofficial broadcasts. The purpose of this research is 1) to show language interference on private radio broadcasters in DKI Jakarta, and 2) to describe language interference on private radio broadcasters in DKI Jakarta. This research used descriptive qualitative method that describing the grammatical and lexical interference of private radio broadcasters in DKI Jakarta. This research applied Weinreich's theory (1970), which stated that interference is the use of two languages by someone which can sometimes lead to deviations from the norms of each language. The results show that in broadcasting there are 1) nonIndonesian grammatical interference into Indonesian, 2) non-Indonesian lexical interference into Indonesian.

Keywords : Bilingualism, grammatical interference, lexical interference.