Intensive Care Unit (ICU) nurses prescribe medication for patients in many countries. However, there is still no evidence on the legitimacy of nurse prescribing roles in the healthcare system of Iran. This qualitative study with 30 experts was conducted to explore the experiences regarding the expanding role of prescribing medication by the ICU nurses. Data were collected through 31 individual semi-structured interviews and analyzed using the conventional content analysis method by MAXQDA 10. One major theme, “applicability of prescribing medication by ICU nurses”, together with three sub-themes of “facilitators”, “potential risks of nurse prescribing” and “the professional pathway”, emerged. The use of successful global experiences, patient-oriented healthcare system policies, current culture and positive professional position of nurses, physician shortage, and high capacity of ICU nurses appeared as facilitators to perform the new role in our context. For the expansion of the new role, different professional pathways such as discussion with physicians and special groups with conflicts of interests, training qualified nurses in this area, and gradual development were proposed by the participants. The next step of the research is to prepare a set of standards for the prescription of medication by the ICU nurses in our context.