SYNOPSISObjective. This article examines ethnic similarities and differences in profiles of mother–child interaction qualities for low-income African American and Latin American mothers and associations with preschoolers’ emerging school readiness. Design. Videotaped mother–child interactions were collected at age 2.5 years from a sample of African American (n = 192) and Latin American (n = 210) families. Profiles of maternal behavior were identified in person-centered within-group analyses of five ratings of maternal behavior from the videotaped interactions. Mothering profile groups were examined for relations to child receptive language, behavior problems, and pre-academic school readiness measured at age 3.5 years. Results. Latent class analyses yielded three similar profiles in the two ethnicities identified as Child-Oriented, Directive, and Harsh-Intrusive mothering, and a fourth profile of Withdrawn mothering only among the African American mothers. For African American children, Child-Oriented and Directive mothering were each associated with higher pre-academic school readiness and language scores than Harsh-Intrusive or Withdrawn mothering. For Latin American children, Child-Oriented mothering was associated with fewer child behavior problems than Harsh-Intrusive mothering, and higher school readiness scores than Directive mothering. Conclusions. Both similarities and differences were found between African American and Latin American families in observation-based mothering profiles and their linkages with preschoolers’ school readiness.