Keywords: Code Switching, Kindergarten, Kindergarten Teacher This descriptive qualitative research was conducted to find out the types, functions, and reasons of code switching from English to Indonesian language used by the teacher at Kiddos English School. To obtain the data, the observation was carried out to see the types of code switch which was derived from the theories of Hudson (1980), Wardhaugh (2006) and Hoffman (1991), and to see the function which was taken from the theory of Gumpers (1982). Interview was also conducted to find the teacher’s reason of using code switch that was adapted from the theory of Hoffman (1991). The result showed that there were six types, five functions, and seven reasons of code-switching found. The most frequent type of code switching used was Conversational code switching (50.02%), and the least frequent type was Metaphorical code switching (2.77%). The function of code switching that most frequently occurred was Reiteration (70.25%), and the least frequently occurred was Addressee Specification (0.83%). The reasons of the use of code-switching covered the need to talk about a particular topic, the necessity of quoting somebody else, being emphatic about something, the essential of using interjection, the need to use repetition for clarification, necessity of intention in clarifying the speech content for the interlocutor, and to express group identity. In summary, the teacher generally employed conversational code-switching and used code-switching to restate a message from one language to another. Also, the reasons of using code-switching were meant to assist the students’ learning.