working memory.to verify the performance of children with normal speech development (NSD) and with evolutional phonological deviation (EPD), in tasks which demand the use of working memory.as a research instrument, subtest 5 of the Illinois Test of Psycholinguistics Abilities (ITPA) was used, as well as the meaningless word repetition test. The answers were analyzed based on the results of the digit repetition test and the meaningless word repetition test, comparing the performance of both groups.when comparing the groups, it was verified that the performance of children with EPD is lower than children with NSD in both of the analyzed tests.the obtainded results confirm that the working memory is fundamental for the development of speech and for the phoneme choice when producing words.