The purpose of this study was to determine the application of the Librarian Profesional Ethics in Service Practice in The Library in The North Kolaka Area. The approach used in research is to use a qualitative descriptive approach. Which consisted of 8 informants, 3 librarians and 5 users. Data collection techniques used were observation, interviews, and documentation. The results of this study indicate that the application of the Librarian Profesional Ethics in Service Practice Library has been implemented by the Librarians properly in accordance with the rules written in the Indonesian Librarian Code of Ethics especially article 3 paragraph 6 regarding the polite and wise attitude of the Librarian in providing services. This was proven through direct observation and interviews at the North Kolaka Regional Library. Keywords: Library, librarian, librarian ethics