Black and Latine parents play a crucial role in shaping adolescents' math and science motivation and science, technology, engineering, and math (STEM) course taking. However, providing extensive support across various behaviors may not always be feasible nor optimal. Analyzing data from 4,230 Black and Latine families (47% Latine, 46% Black; 50% girls; 70% noncollege educated parents), we identified six distinct parent support profiles using the High School Longitudinal Study of 2009 data set. Four patterns showed higher engagement (high multifaceted supporters, involved academic discussers, moderately encouraging discussers, involved STEM-encouragers), and two exhibited slightly less support (moderately involved academic discussers and moderately involved STEM nonencouragers). Generally, consistent findings emerged for both Black and Latine families concerning the profiles and their relations with adolescents' math and science beliefs in 11th grade and STEM coursework. The moderately encouraging discussers and involved STEM-encouragers profiles correlated with the most positive STEM motivational beliefs and course taking, whereas the moderately involved STEM nonencouragers profile was associated with the lowest motivation and course taking. This suggests that STEM encouragement from parents, combined with other supportive behaviors, may be particularly crucial for Black and Latine adolescents, and high support across all indicators may not be the optimal approach, especially for high-achieving students. (PsycInfo Database Record (c) 2025 APA, all rights reserved).