Previous studies reported conflicting results for the effects of homophony on visual word processing across languages. On finding significant differences in homophone density in Japanese, Mandarin Chinese and English, we conducted two experiments to compare native speakers’ competence in homophone auditory processing across these three languages. A lexical decision task showed that the effect of homophony on word processing in Japanese was significantly less detrimental than in Mandarin and English. A word-learning task showed that native Japanese speakers were the fastest in learning novel homophones. These results suggest that language-intrinsic properties influence corresponding language processing abilities of native speakers.