Background: Several factors were detected in ICU nurses' work system that can hinder their activity. Aim: The aim of the study was to investigate performance obstacles in ICUs nurses at Assuit University Hospitals. Setting The present study was carried out in the intensive care units at seven specialties at Assiut University Hospitals. Subjects: The study sample was 194 staff nurses who were working as bedside nurses in seven ICUs and who were willing to participate in the study. Tools: Data of the present collected through utilizing the following two tools personal characteristic: performance obstacles ICUs questionnaire Results: influential performance obstacles items were that the nursing staff was not enough to handle the number of patient, had difficulty finding a space to sit down and do any paperwork in their unit nurses, complain of the equipment in bad condition and there was a delay in getting medicines for patients. Recommendations: It is recommended that: When planning for a new or renovated critical care units, the health care facility should consults an expert in the field of hospital design as well as taking consideration about nurses and patients needs related to infrastructure of the unit.