Background: In opaque orthographies, such as English, children with low reading skills tend to rely more on semantic information due to their inadequate acquisition of sub-lexical knowledge. This tendency has also been reported for kanji, a non-alphabetic and opaque Japanese orthography. However, previous studies on this phenomenon have had methodological limitations, such as a small number of stimuli in reading tests and insufficient investigation of a consistency effect. This study addressed these limitations and aimed to clarify whether Japanese children with low reading accuracy are characterised by a stronger reliance on semantic information and a smaller contribution to the reading process based on character-to-sound correspondences to the kanji word-reading performance than children with high reading accuracy in reading kanji words. Methods: A total of 129 Japanese students in the fifth and sixth grades participated in this study, and 11 of them had been previously diagnosed with developmental dyslexia. They read an experimenter-created list of kanji words. We tested how frequency, imageability and consistency of character-to-sound correspondences affected children's reading accuracy and error types and how the effects of these variables were modulated by reading accuracy level. Results: For children with lower reading accuracy, the frequency and consistency effects on reading accuracy decreased, whereas the imageability effect was stronger. Children with low reading accuracy frequently did not respond, whereas children with high reading accuracy made word substitution and legitimate alternative reading of component (LARC) errors frequently. Conclusions: The reading processing of children with low reading accuracy is characterised by a stronger reliance on semantic information and a smaller contribution of a reading process based on character-to-sound correspondences to reading performance than that of children with high reading accuracy. Reading characteristics of children with low reading accuracy might be due to their inadequate lexical and sub-word knowledge.