Introduction: The sociocultural diversity in the Brazilian Amazon demands cultural competences from the health professionals. Despite this fact, the nursing care provided to indigenous and non-indigenous people does not differ. The professional and permanent training is verticalized and centered around the operation of services. The competences required by the indigenous health have a technical-care nature. General goal: Develop, implement and evaluate an educational activity mediated by Culture Circles focused on the development of critical cultural competences alongside nurses who work on indigenous health at DSEI Guatoc in the state of Pará. Method: Qualitative intervention study approached through the triangulation of data acquisition, analysis and assessment. Culture Circles were used as research itinerary in the development of the educational activity. Five meetings were held at the CASAI Icoaraci, CASAI and Polo de Marabá, and seven meetings were held at CASAI and Polo Paragominas. Among the participants, there were 19 nurses who were working in these services for more than a year continuously without taking a work leave. The investigation started after the approval from the Research Ethics Committee of the University of São Paulo Nursing School. The results of the participants' profile and the self-evaluation instrument were collected using Microsoft Excel, version 2007, for descriptive analysis. The qualitative results were organized using the free version of Atlas Ti and analyzed according to the dialectical hermeneutics method. Results: Most of the participants were women, northerner, black and colored, married; alumni from private universities; specialized in indigenous health and in a work contract under the general labor law, known as CLT. The self-evaluation did not show biased results towards socially accepted responses, which can demonstrate critical and reflective self-evaluation. During inquiry stage of the educational activity, mediated by culture circles, communication issues emerged as generative theme; in the thematization stage, the functional interculturality; and in the problematization, it became evident that the participants developed transitive consciousness owing to the analysis of the problem-posing situations, which resulted in the production of a idiomatic booklet. Discussion: The knowledge-regulation is the guiding principle for the work of the participants, yet they presented transitive consciousness during the culture circles. The cognitive domain brought out sensibleness/consciousness and cultural knowledge due to the manifestation of reflection, critical thinking and mobilization towards inter-knowledge, acknowledgement and self-knowledge. These pointed to a closeness to the ecology of knowledge and the knowledge emancipation. Conclusion: Through the educational activity, mediated by the culture circles, it was possible to understand that the cultural competences from a critical perspective is an educational process based on dialogue which can be described as collective, coll...