Introduction: Critical care information systems are designed to replace paper charts, interact with other clinical wards of hospital, and to better care for patients. This qualitative study was performed to obtain the perception of intensive care unit nurses about the efficiency of information systems. Method: In this qualitative study, data were collected through semi-structured and in-depth interviews and analyzed by content analysis and constant comparison method. Participants were 30 nurses from intensive care units of affiliated hospitals of Semnan University of Medical Sciences, Iran. Purposeful sampling method was used and continued until data saturation. Results: The several themes that emerged from the interviews were divided into inhibiting factors and facilitating factors. Facilitators included the acceleration of nursing operations, reduction of costs, and the increasing of nurse’s role in patient care. The inhibiting factors were repetition of tasks and low computer literacy of the staff. Conclusion: Nurses were faced with challenges in the use of information systems indicating the lack of quality of the information system. It seems that strengthening facilitators and resolving hardware and software problems can increase intensive care staff’s acceptance of this information system and reduce their cultural resistance toward it.