Academic self-concept has been conceptualized as a multidimensional and hierarchical construct. Previous research has mostly focused on its multidimensionality, distinguishing between verbal and mathematical self-concept domains, and only a few studies have examined the factorial structure within specific self-concept domains. The present study aims to extend the scarce evidence of the simultaneous operation of multidimensionality and hierarchy within language self-concepts. Skill-specific (i.e., reading, listening, speaking, and writing) and global self-concept measures for German as students’ native language and English and French as students’ foreign languages were administered to a sample of 4,257 ninth-grade German students. Confirmatory factor analyses demonstrated better levels of fit for multidimensional models with highly correlated but separate factors for each skill-specific self-concept compared to unidimensional models. The skill-specific facets could be aggregated into a higher order factor for each language, demonstrating a hierarchical structure. Differential gender effects on the various skill-specific self-concept facets provided further evidence of the multidimensional nature of language self-concepts, although differential relations to skill-specific achievement measures were not found. The high correlation between the higher order and global self-concept factors as well as similar gender effects and relations to achievement supported the notion of the similarity of both constructs. A comparable pattern of results emerged across the 3 languages, but detailed inspection indicated that multidimensionality seems to be more pronounced in the native language domain (German). The findings of the study are discussed regarding their implications for the assessment of language self-concepts and future research on the structure of language self-concepts.