The purpose of this study was to examine the role and nature of phonology in silent reading of Japanese sentences. An experiment was conducted using a Japanese sentence acceptability judgment task. One important finding was that participants more rapidly rejected homophonic sentences in which one two-kanji compound word was replaced by its homophone word than non-homophonic sentences. In the latter, the word was replaced by a non-homophone spelling control; that is, we observed a homophone advantage. Participants were able to identify the correct word easily through foil's homophonic mate. This indicated that activated phonology played a role in the Japanese sentence acceptability judgment task and it contributed to the error detection/recovery process. Another important finding was that the homophone facilitation effect remained under articulatory suppression. It confirmed that phonology was activated at an early stage as abstract, non-articulatory phonology.