Economists and policymakers believe that households’ and firms’ expectations of future inflation are key determinants of actual inflation. This paper applies the ARDL model and nonlinear ARDL model to long-term inflation-targeting policy mechanisms in the United States and China to assess the impact of oil price dynamics and asymmetries on inflation expectations, as well as the difference of this impact before and after the COVID-19 pandemic. In order to show the significant role of the COVID-19 outbreak, this paper includes the data from 2010 to 2021 and takes the pandemic period as a structural break. Taking oil price changes as a variable of interest, and introducing some other significant variables, we find that during the pandemic, the positive impact of oil price shock on U.S. inflation expectations has enhanced, whereas the positive impact on Chinese inflation expectations has weakened. There is also sufficient evidence of the existence of the asymmetric effects of oil price changes on inflation expectations in both countries, but the positive oil price change in the United States has always played a larger role than the negative oil price shock. In China, the impact of positive oil price shock was greater than that of negative oil prices before the epidemic and the effect of negative oil price shocks has increased significantly in the COVID-19 regime.