Background: An internship project can be considered as a useful step for nursing interns in the transition period and bridge the theory-practice gap in nursing. Since the acquisition of professional competence and skills by students is essential, the present study attempted to provide a deep understanding of nursing students’ experiences. Methods: This study was conducted using a qualitative content analysis approach in the School of Nursing of Kerman University of Medical Sciences in 2020. The participants in the research sample were senior undergraduate nursing students who were selected using purposive sampling. The data were collected through semi-structured interviews with the participants and each interview lasted 60 to 90 minutes. A total of 27 interviews were conducted with 25 students. The collected data were analyzed using a qualitative content analysis method (Graneheim & Lundman, 2004). MAXQDA 20 software was also used to analyze the qualitative data. Results: The core category that emerged from the analysis of qualitative data was "implementing an internship program; a step to bridge the theory-practice gap", which was divided into three main categories: "transferring knowledge and experiences", "promoting the cooperation between the faculty members and the hospital staff", and "improving the process of clinical care". Conclusion: Internship programs that are considered a new training technique can increase cooperation between nursing schools and contribute to promoting nursing knowledge in nurses by supporting students and promoting their scientific skills.