Purpose: The purpose of this study was to examine the effects of discharge planning on patient satisfaction, the readmission rate and preparedness for discharge in the elderly admitted to the emergency room (ER) for pulmonary disease. Methods: A quasi-experimental intervention study design was used. Older adults with pulmonary health problems in the ER in one general hospital were randomly allocated to either an experimental (n=21, 74.2 years) or control group (n=19, 70.7 years). The experimental group participated in a discharge planning program by a geriatric nurse practitioner. Data were collected from medical records, physical measurements and structured questionnaires including information on demographics, patient satisfaction, readmission, and preparedness for discharge. Results: Participants in the experimental group had significantly better outcomes with regard to patient satisfaction with nursing services (p=.003) and preparedness for discharge (p=.034). However, there was no significant effect on the readmission rate (p=.392) Conclusion: The results suggested that a discharge planning program could bolster nursing service satisfaction and preparedness for discharge in older patients admitted to the ER for pulmonary health problems. To clarify the effects of discharge planning on older patients admitted to the ER, a larger sample population, better instruments for various measures, a new manual on discharge planning and frequent follow-up will be necessary.