Platelet aggregation has been associated with COVID-19 pathogenesis. In older patients hospitalized for SARS-CoV-2 pneumonia, we aimed to investigate the association between aspirin use before admission and the risk of in-hospital all-cause mortality. We performed a retrospective international cohort study in five COVID-19 geriatric units in France and Switzerland. Among 1,357 consecutive hospitalized patients aged 75 or older and testing positive for SARS-CoV-2, we included 1,072 with radiologically confirmed pneumonia. To adjust for confounders, a propensity score for treatment was created, and stabilized inverse probability of treatment weighting (SIPTW) was applied. To assess the association between aspirin use and in-hospital 30-day mortality, SIPTW-adjusted Kaplan-Meier and Cox proportional hazards regression analyses were performed. Of the 1047 patients with SARS-CoV-2 pneumonia and median age 86 years, 301 (28.7%) were taking aspirin treatment before admission. One hundred forty-seven (34.3%) patients who had taken aspirin died in hospital within 1 month vs 118 patients (30.7%) without aspirin. After SIPTW, aspirin treatment was not significantly associated with lower mortality (adjusted hazard ratio: 1.10 [0.81-1.49], P = .52). Moreover, patients on aspirin had a longer hospital stay and were more frequently transferred to the intensive care unit. In a large multicenter cohort of older inpatients with SARS-CoV-2 pneumonia, aspirin use before admission did not appear to be associated with an improved prognosis.