The size and especially the growth of the Latino population in the United States are associated with anti-Latino and anti-immigrant attitudes. Findings from a recent line of experimental work suggest that Latino growth may also be associated with Whites’ anti-Black attitudes. Racial status threat could account for this association if Whites view Latino growth as a potential challenge to their status within a multi-group system that includes Blacks. Alternatively, or in addition, by engendering instability and uncertainty, Latino growth may promote ideological conservatism, which itself predicts racial attitudes. Building on prior work, this study examines the association between real, local Latino population growth––as opposed to manipulated or perceived growth––and Whites’ anti-Black resentment for a nationally representative sample of White Americans. Using data from the 2018 Cooperative Congressional Election Survey, the study finds that Whites in counties where the Latino population grew more report stronger anti-Black resentment. They are also more likely to perceive a threat to Whites’ racial status and to endorse ideological conservatism. Perceived threat and conservatism each partially account for the association between Latino growth and anti-Black resentment, suggesting the effect of Latino growth on anti-Black resentment is mediated through both channels.