We examine whether and to what extent the presidential COVID-19 sentiment (PCS), constructed based on the former President Trump’s tweets, has influenced the public’s risk perception regarding COVID-19. We find that during the COVID-19 pandemic, PCS is negatively associated with social distancing behaviour in the Republican counties but is positively associated with social distancing behaviour in the Democratic counties. Our finding supports the view that individuals’ risk perception is influenced by the information they receive from politicians through social media, with the impact exhibiting as variations with respect to the individuals’ position on the political spectrum.