Studies using cross-country comparisons argue that the benefits of parental involvement depend on the educational setting in which it exists. However, contextual and cultural differences likely transcend the differences observed across educational systems. Instead, this study compares the educational advantages of parents’ school-based involvement across different admissions systems in a single society. I draw on the case of Taiwan, where high schools select students through both applications and exams. The findings show that parental involvement is positively associated with children’s high school placements in both admissions systems. However, students with privileged class backgrounds reap greater rewards from parental involvement in the application system than those in the exam system. The marginal effects of parental involvement in applications systems are also considerably stronger than those in exam systems. The results of direct comparisons illustrate that institutional settings critically shape the benefits students accrue from parental involvement. Conceptualizing parental involvement as a measure of cultural capital, this study highlights educational systems’ role in conditioning how cultural capital contributes to educational inequality.