OBJECTIVES: Preventive care has the potential to improve health status thus reduce the use of the expensive emergency room care. The Affordable Care Act (ACA) expanded coverage for preventive services. This study examines the association between ACA-covered preventive care and emergency room (ER) visits and costs. METHODS: A retrospective, cross-sectional study was conducted using the 2009 and 2013 Medical Expenditure Panel Survey (MEPS). Four items from MEPS asked about the use of blood pressure screening, cholesterol screening, influenza vaccine, colorectal cancer screening. Andersen’s health care utilization model was employed to examine the relationship between ACA-covered preventive care service, ER room visits, and costs. Multiple regression was used to control for covariates. RESULTS: Approximately 14.0% of the participants reported receiving ER care in 2013 with median of one visit and expenditure of $1434.66; while 13.6% of the participants reported receiving emergency room care in 2009 with median of one visit and expenditure of $1413.68. The receipt of ACA-covered preventive service was not significantly associated with the number of ER visits both for 2009 and 2013(p>0.05). Blood pressure check was negatively associated with ER costs in 2009(p=0.0027). But all other services were not significantly associated with ER costs for 2009 and 2013(p>0.05). CONCLUSIONS: The insignificant association between ACA covered preventive care service and ER visits or costs indicates that the power of preventive care in reducing overall health cost might be limited. Future longitudinal research is needed to evaluate the impact of ACA covered preventive care.