This study examines the role of perceived phenotypic racial stereotypicality and race-based social identity threat on racial minorities’ trust and cooperation with police. We hypothesize that in police interactions, racial minorities’ phenotypic racial stereotypicality may increase race-based social identity threat, which will lead to distrust and decreased participation with police. Racial minorities (Blacks, Latinos, Native Americans, and multi-racials) and Whites from a representative random sample of city residents were surveyed about policing attitudes. A serial multiple mediation model confirmed that racial minorities’ self-rated phenotypic racial stereotypicality indirectly affected future cooperation through social identity threat and trust. Due to the lack of negative group stereotypes in policing, the model did not hold for Whites. This study provides evidence that phenotypic stereotypicality influences racial minorities’ psychological experiences interacting with police.