Such neighborhood has a unique landscape, marked since its beginnings, at the end of the 19 th century, by the presence of several ethnic groups. It is a social microcosm, which received large groups of immigrants throughout its history, bringing their own unique cultural characteristics to the area. Nowadays, Koreans and Bolivians have become the two most significant immigrant groups among the population living and working in the area. Both groups are integrated into the material base of clothing industry, since textile manufacture is one of the economic structural axes of Bom Retiro. The establishment of a Family Health Unit in Bom Retiro, besides evoking a reflection on the potential and difficulties for the Family Health Program in large urban areas, also brings issues related to the presence of these immigrants to the discussion, requiring various analyses on the theme of interaction between health care professionals and users. Thus, the purpose of this work is to analyze the interaction between the Family Health Program and Korean and Bolivian immigrants located in the neighborhood of Bom Retiro, in the city of São Paulo, which results in a unique experience. This is a qualitative research, which used the technique of semi-structured interviews with three Koreans, three Bolivians and six health care workers from the Bom Retiro Family Health Unit. With regard to the analysis of the interviews, the technique of thematic content analysis was used, considering the conjunctures, reasons and logic, as well as actions and interrelations established between the collective and the institutions. The results show the particularities of the insertion of these two immigrant groups in Bom Retiro, and highlight in particular the dimensions of the world of work, housing and the large spatial mobility of immigrants, requiring Family Health Program's map-based logic to become more flexible, with the enlargement of the concept of family and several communication strategies used by the Family Health team to establish communication with the Korean and Bolivian immigrants.