Language, as a tool of communication is needed to connect people in a community. That is why it is important to study language and things related with it. The development of language is influenced by the society itself, so they create many kinds of language variation, including dialect, jargon, slang, colloquial, vernacular, accent, pidgin, and register. The writer discussed one of those language variations that is register. Register is a stylistic variant of a language appropriate to a particular social setting. Register is often used by people in certain place. The writer studied about the registers used by immigration officer of immigration office in Malang. \ud
This study used descriptive qualitative design to get the information. The subjects of the study were the three officers who involved in immigration office. In this research, the writer chose them because they have good knowledge on register used in that office. This used three kinds of instruments. There were nonparticipant observation, structured interview and document. They were used to seek the information and to get the necessary data related to register used by officer. \ud
In analyzing data, the writer analyzed the data by interpreting, synthesizing, categorizing, and organizing data into patterns that produce a descriptive and narrative synthesis. \ud
This study found out that total registers used by officers of immigration office are 22 registers. From the 22 registers, 9 registers grouped into formal registers and 13 registers can be grouped into informal registers. In this finding, another type of registers such as overformal register, motherese, and reporting register were not found
