Metalinguistic awareness (MLA) is a predictor of adult foreign language (FL) learning in instructed settings. Following Bialystok and Ryan (1985) two-component model of MLA, we distinguish ML analysis as the ability to compare and select language items from ML control as the ability to detect and manipulate rule-based linguistic patterns. So far, there is little evidence how components of MLA interact, and how they affect learning outcomes in early FL learning. In this paper, we investigate the effects of MLA on FL learning of English in primary school, where learning is mostly oral and proficiency in the target language is still rudimentary. We tested 200 students in German public primary schools on English vocabulary and grammar. Metalinguistic (ML) analysis was assessed in an interview, while ML control was operationalized in phoneme manipulation and letter fluency tasks. In addition, we assessed personal, cognitive, and social covariates. Results from linear mixed effects regression analyses indicate that (a) ML control predicts ML analysis skills, (b) ML analysis fosters FL vocabulary outcomes, and (c) ML control benefits grammar skills. We discuss theoretical and practical implications.