(1) Describe the development process for the ChatGPT-based Virtual Reality Obstetric Nursing Communication Simulation System (ChatVR-ONCS), (2) explore its effects on communication competence in nursing students and (3) determine the perceived usability of ChatVR-ONCS and learning experiences in nursing students. Communication is crucial in obstetric nursing, yet traditional teaching methods often fail to enhance students' relevant skills due to their lack of realism. Therefore, developing a training tool that offers high usability, immersive experiences and real-time interactivity is vital. Mixed research methods were applied involving pre- and post-tests within a single group of 52 nursing students at a Taiwanese science and technology university as well as a focus group. The Visual Analog Scale for Communication Self-Confidence, Maternal and Newborn Care Communication Assessment Form and System Usability Scale were administered before the intervention (T0), immediately after the intervention (T1) and 3 months after the intervention (T2). A focus group was conducted after T2 to explore their learning experience and obtain feedback on the proposed system. The participants' communication self-confidence, communication skills and ratings on system usability significantly improved after the ChatVR-ONCS intervention, with the effects lasting for 3 months. The qualitative analysis demonstrated a high level of user satisfaction and the positive effects of the system in promoting communication skill development. By integrating artificial intelligence and virtual reality technologies, ChatVR-ONCS not only significantly enhances the effectiveness of nurse-patient communication training but also provides empirical support for digital development in nursing education.