Background <p>Advances in science and technology have turned the modern healthcare system into a challenging environment with many ethical dilemmas. Internship nursing students experience many ethical issues in the clinical environment. The present study explored the experiences of Iranian internship nursing students in confronting ethical issues.</p> Methods <p>The present study is a qualitative inquiry with a conventional content analysis approach. A total of 15 internship nursing students (six females and nine males, semesters 7 and 8) were selected via purposive sampling with maximum variation from the nursing and midwifery faculty at Golestan University of Medical Sciences, northern Iran. Data were collected using semi-structured interviews over eight months. Graneheim and Lundman’s qualitative conventional content analysis approach was used for data analysis. MAXQDA version 2022 was utilized for data management. The trustworthiness of the data was ensured by four criteria given by Lincoln and Guba.</p> Results <p>Qualitative data analysis led to 792 initial codes, which were reduced to 262 after removing duplicates. Subsequent analysis resulted in 7 sub-categories and 3 main categories, including “Insufficient Ethical Preparation,” “Inadequate Ethical Reasoning Skills,” and “An Ineffective Ethical Atmosphere in the Clinical Environment.” Ultimately, the main theme of “Limited Ethical Maturity of Students in Ethical Issues” was extracted.</p> Conclusion <p>Internship nursing students enter the educational environment with inadequate preparation and limited ethical maturity, which often leads to passive behavior when faced with ethical issues. Considering the non-educational clinical environment and the identified issues in the academic structure, reviewing the curriculum of professional ethics in nursing in Iran seems necessary.</p>