The present paper takes into account the Variation Theory, proposed in the 60 s by the linguist William Labov, to explain the palatalization phenomenon on /S/ fricative in coda position in the speech community of Macapá-AP. Recognizing the language variability, many studies have been carried out in order to identify, describe and explain the linguistics phenomena which occur in Brazilian Portuguese. The /S/ palatalization phenomenon, for example, is a process which had been object of study in speeches of diferent regions in Brazil: Rio de Janeiro-RJ (CALLOU & MARQUES, 1975); Natal-RN (PESSOA,1986); Recife-PE, Salvador-BA e Rio de Janeiro-RJ (CALLOU & MORAES, 1996); Corumbá-MS (SILVA, 1996); João Pessoa-PB (HORA, 2000); Salvador-BA (...