The COVID-19 pandemic, caused by the novel human coronavirus SARS-CoV-2 coronavirus, attacks various organs but most destructively the lung. It has been shown that SARS-CoV-2 entry into lung cells requires two host cell surface proteins: ACE2 and TMPRSS2. Downregulation of one or both of these is thus a potential therapeutic approach for COVID-19. TMPRSS2 is a known target of the androgen receptor, a ligand-activated transcription factor; activation of the androgen receptor increases TMPRSS2 levels in various tissues, most notably the prostate. We show here that treatment with the antiandrogen enzalutamide – a well-tolerated drug widely used in advanced prostate cancer – reduces TMPRSS2 levels in human lung cells. Further, enzalutamide treatment of mice dramatically decreased Tmprss2 levels in the lung. To determine therapeutic potential, we assessed uptake of SARS-CoV-2 Spike protein pseudotyped lentivirus and live SARS-CoV-2 into human lung cells and saw a significant reduction in viral entry and infection upon treatment with the antiandrogens enzalutamide and bicalutamide. In support of this new experimental data, analysis of existing datasets shows striking co-expression of AR and TMPRSS2, including in specific lung cell types that are targeted by SARS-CoV-2. Together, the data presented provides strong evidence to support clinical trials to assess the efficacy of antiandrogens as a treatment option for COVID-19.