Recent research has shown that the knowledge of letter names plays an influential role in writing acquisition skills as children make their way through school. This knowledge contributes to the initial development of spelling skills and the identification of written words, and through mechanisms that are no doubt interdependent; it also helps children learn letter-phoneme relationships and phonemic sensitivity. This study examines the relationships between the knowledge of letter names and learning the sound of each letter. The participants were Francophone pre-readers from two grade levels (4-5 year-olds and 5-6 year-olds). Their task was to identify pseudo words with the forced-choice technique. The students had to identify words the experimenter said (e.g., /bok/) from a pair of pseudo words that only differed by one consonant (e.g., BOC vs. VOC) The children knew the names of the consonants used in the study, but not their sounds. Three variables were manipulated: the position of the target consonant in the pseudo word (initial vs. final); the type of name of the target consonant (consonant-vowel vs. vowel-consonant); the linguistic structure of the pseudo words (CVC vs. CCV). The results demonstrated that at the age of 5-6, the vast majority of the pre-readers and a significant number of 4-5 year-olds were able to use the letter-phoneme relationships to distinguish written words. The discussion envisages theoretical implications related to learning the sound of the letters, and outlines a few educational suggestions.