The inhibitory effect of positional syllable frequency is a well-known phenomenon in visual word recognition: words with high-frequency syllables require extra time for deactivating the lexical syllabic neighbors. The inhibitory effect implies that a connection exists between graphemes, phonemes, the first syllable, and the phonological lexicon. However, experimental results of the first developmental stages of occurrence are scarce and inconclusive. A second- and fourth-grade sample of typical school readers participated in a lexical decision task containing high/low frequency words and high/low syllable frequency words. Our primary hypothesis was that the inhibitory effect would be found on both school grade groups. We did not predict significant differences in magnitude of effect between second- and fourth-grade participants. A general inhibitory effect was found, and separate analyses by school grade groups also indicated significant inhibitory effects. Furthermore, second- and fourth-grade children showed small sizes of the inhibitory effect, resembling the sizes found in adult normal readers. Our results suggest that Spanish readers reach a functional connection between syllables and words at an early stage. The straightforward theoretical implication is that the inhibitory effect relies heavily on the structural properties of the lexical access system that are acquired at an early age.