Several studies have indicated that dyslexics show a deficit in speech perception (SP). The main purpose of this research is to determine the development of SP in dyslexics and normal readers paired by grades from 2nd to 6th grade of primary school and to know whether the phonetic contrasts that are relevant for SP change during development, taking into account the individual differences. The achievement of both groups was compared in the phonetic tasks: voicing contrast, place of articulation contrast and manner of articulation contrast. The results showed that the dyslexic performed poorer than the normal readers in SP. In place of articulation contrast, the developmental pattern is similar in both groups but not in voicing and manner of articulation. Manner of articulation has more influence on SP, and its development is higher than the other contrast tasks in both groups.