Background: TMPRSS2, a cell surface protease which is commonly upregulated in prostate cancer (PC) and regulated by androgens, is a necessary component for SARS-CoV2 cellular entry into respiratory epithelial cells. PC patients receiving ADT were reported to have a lower risk of SARS-CoV-2 infection. However, whether ADT may have an impact on the severity of COVID-19 illness in this population is poorly understood. Methods: In this study performed across 7 US medical centers, we retrospectively evaluated patients with active PC and SARS-COV-2 viral detection by PCR between 03/01/20 and 05/31/20. We collected information on demographics; medical comorbidities; medications; PC Gleason score at initial diagnosis; presence of active disease, metastases, and castration resistance; ADT use as defined by GnRH analog or antagonist within 3 months or castration levels of testosterone < 50 ng/dL within 6 months of COVID-19 diagnosis, or history of bilateral orchiectomy; active non-ADT systemic therapies including, but not limited to, androgen-receptor-targeted therapies and chemotherapy; and COVID-19-related outcomes including hospitalization, supplemental oxygen use, mechanical ventilation requirement, WHO COVID-19 ordinal scale for clinical improvement, follow-up duration, and vital status. Multivariable mixed-effect logistic regression was performed to evaluate any difference in COVID-19 clinical outcomes between patients on and not on ADT. Survival analysis was done using adjusted Cox proportion-hazards regression model. All tests were two-sided at 0.05 significance level. Results: We identified 465 evaluable patients with median age of 71 (61-81) years. Median duration of follow-up was 60 (12-114.2) days. In this follow up period, there were 195 (41.9%) hospitalizations and 111 (23.9%) deaths. When adjusted for age, BMI, and PC clinical disease state, overall survival (HR 1.28 [95%CI 0.79-2.08], P = 0.32), hospitalization status (HR 1.07 [0.61-1.87], P = 0.82), supplemental oxygen use (HR 1.29 [0.77-2.17], P = 0.34), and use of mechanical ventilation (HR 1.07 [0.51-2.23], P = 0.87) were not statistically different between ADT and non-ADT cohorts. Similarly, in subgroup analysis, no statistical difference in overall survival was found between ADT and non-ADT cohorts for hospitalized patients (HR 1.42 [0.82-2.47], P = 0.21) and those receiving supplemental oxygen (HR 1.10 [0.65-1.85], P = 0.73). Conclusions: In this retrospective cohort of PC patients, use of ADT prior to COVID-19 diagnosis does not protect against severe COVID-19 illness as defined by hospitalization, supplemental oxygen use, or death. Further preclinical work in understanding TMPRSS2 expression and androgen regulation in respiratory epithelial cells is needed. As well, longer clinical follow-up and additional clinical studies inclusive of prospective data are warranted to fully address this question.