Our study focused on the nature and the origin of reading disorders in French dyslexic children. Nowadays, two leading theories coexist: one claims that dyslexic children would have degraded phonological representations while the other one proposes difficulties to access them. We were interested in how the phonological representation of the syllable could be used and accessed in French dyslexic children. Ten French dyslexic children with phonological disorders compared to twenty controls (chronological age and reading level) completed two tasks with or without lexical access: a visual masked priming paradigm in a lexical decision task and a visual syllable detection task. Both tasks allowed us to study whether the syllable is a pre-lexical and segmental reading unit in dyslexic children. We considered as crucial factors the initial phonological and orthographic syllable frequency, the lexical frequency and the syllable structure to select words, and the reading level. Our results showed that they use syllables as pre-lexical and segmental units as normal-readers did. But sensitivity to syllables appears later in dyslexic children. As reading experience increases, speed and accuracy improve toward the use of a syllable-based processing. Then, the initial – phonological – syllable frequency has facilitatory effects in reading level-matched controls. But it has inhibitory effects in chronological age-matched controls and, to a lesser extent, in dyslexic children in the task that required a lexical access. However, the initial syllable frequency remains facilitative in the non-lexical task. Our results showed that while dyslexic children were slower, their accuracy and sensitivity to statistical factors were as close as those found in normal-readers. We discuss our results toward the hypothesis that some French dyslexic children might have well-specified phonological syllable representations but degraded – or disrupted – access to them.