Perceptions of human changeability may be particularly relevant to immigration attitudes. Building upon research showing that beliefs about the fixedness versus malleability of human characteristics (entity versus incremental beliefs) shape intergroup attitudes (e.g., Levy, Stroessner, & Dweck, 1998), my program of research explored how these beliefs shape attitudes toward immigrants and immigration policy. Across five studies, using UC Berkeley student and national adult samples, I assessed participants' entity (versus incremental) beliefs regarding the fixedness or malleability of human characteristics, levels of prejudice, and attitudes toward immigrants and immigration policy. Relative to incremental beliefs, entity beliefs were associated with stronger perceptions that immigrants are incapable of assimilating into U.S. society, greater feelings of threat toward immigrants, more negative emotions toward immigrants, less feelings of warmth toward immigrants, stronger endorsement of legal punishment for undocumented immigrants, and more prejudice toward immigrants. Implications of entity (versus incremental) beliefs for immigration policy and reform are discussed.