This study examined differences between successful and unsuccessful foreign language learners in college. It found that unsuccessful learners performed significantly poorer on tests of phonological processing and grammar/syntax in their native English language. Specifically, unsuccessful learners had more difficulties identifying single words, synthesizing sounds, spelling, and writing grammar compared to successful learners. The results suggest that weaknesses in phonological and syntactic skills in one's native language may indicate potential challenges with learning a foreign language. Further research is needed with larger samples.