This study examined the relations between normative developmental changes of familism values and later internalizing and externalizing behaviors in Latinx adolescents from an emerging immigrant community. The sample included 547 Latinx adolescents (55.4% female; baseline M[subscript age] = 12.80; SD = 1.03) residing in the Southeastern United States. Results from latent growth models indicated that higher initial levels of familism values (intercept) and slower declines (slope) in familism values across adolescence predicted lower internalizing and externalizing behaviors at a later time. These associations generalized across adolescent gender (boys and girls) and ethnic background (Mexican-origin vs. other Latinx-origin). This work highlights the impact of variation in normative developmental changes in familism values on adjustment among Latinx adolescents in an emerging immigrant community context.