The frightening experience in critical care units, whether it be associated with the disease process or related to the critical care environment, has an important impact on clients’ recovery and rehabilitation. A comparative descriptive study was conducted in the critical units of two major hospitals in Hong Kong to assess the perception of stressors by patients and nurses. A Chinese version of the Intensive Care Unit Environmental Stressor Scale (ICUESS) was used. Significant similarities and differences were noted between patients and nurses on their perceptions of stressors in the critical care environment. Critical care nurses, apart from maintaining their efforts to minimize the negative effects of the stressful critical care environment, needed to equally focus on the patients’ psychological needs through measures in re-establishing patients’ self-control and minimizing the emotional stress.