Introduction: Coronary artery dissection is an emergency condition due to a tear in the coronary arterial wall, and it’s an uncommon cause of acute coronary syndrome. The Effect of Obesity on the outcome of acute coronary artery dissection is poorly documented. Hence, our study sought to estimate the impact of Obesity on clinical outcomes of hospitalizations of patients with acute Coronary artery dissection using the national database. Methods: We queried the National Inpatient Sample (NIS) database from 2016 to 2019. The NIS is the largest inpatient hospitalization database in the United States. The NIS was searched for hospitalization of adult patients with acute Coronary artery dissection as a principal diagnosis with and without Obesity as a secondary diagnosis using ICD-10 codes. The primary outcome was inpatient mortality. The secondary results were Acute kidney injury (AKI), Cardiogenic shock (CS), Cardiac arrest (CA), Total hospital charge (THC), and length of stay (LOS). Multivariate logistic and linear regression analyses were used accordingly to adjust for confounders. Results: About 2440 patients were admitted for acute Coronary artery dissection; 17.4% (425) had underlying obesity. Cohorts with obesity vs No obesity had a mean age of 52.9 years [CI 50.4 - 55.5] vs 55.9 years [CI 54.5 - 57.4]; male (20% vs 25.8%), female (80% vs 74.2%); white (71.3% vs 73.3%), black (21.3% vs 12.0%), and Hispanic (6.3% vs 7.8%). Compared to patients without obesity, patients admitted with coexisting obesity had similar inpatient mortality (7.1% vs 3.2%, AOR 3.22, 95% CI 0.74 - 13.88, P=0.118), AKI (15.3% vs 9.9%, P 0.357), CS (9.4% vs 11.2% P=0.098), CA (5.9% vs 5.0% P=0.530), THC (IRR 0.94, 95% CI 0.64 - 1.37, P=0.738), and LOS (IRR 0.79, 95% CI 0.59 - 1.05, P=0.107). Conclusions: Patients admitted primarily for acute Coronary artery dissection with co-existing Obesity had similar inpatient mortality, AKI, CS, CA, THC, and LOS compared to patients without Obesity.