This dissertation focuses on the comprehension of the 3rd person reflexive and referential pronouns by Brazilian Portuguese-speaking children. The constraints of the Principles A and B of the Biding Theory are considered from a psycholinguistic perspective, which takes into account the relative accessibility of potential antecedents of those forms in the working memory during sentence/discourse processing. The reflexivity theory (Reinhart and Reuland,1993) is a major reference, for being compatible with a language acquisition procedure whereby reflexive forms are represented as bound anaphors via the identification of reflexive predicates at the semantic interface. The distribution of anaphors and clitic/stressed pronominals in BP is considered. Three picture identification experiments with children (3-7 years old) and one with adults are reported. The results of the Experiments 1 and 2 suggest that se is recognized as a reflexivity marker at an early age; that 5 year olds interpret it locally in embedded clauses; and children s susceptibility to the presence of an intervening element in the binding domain. The results of Experiment 3 (with adults and children) suggest that the marking of reflexivity by si (a non-verbal argument anaphor, mainly with the intensifier mesmo), and ele(a) mesmo(a) favor local interpretation. Regarding the stressed pronoun, it was verified the main clause subject is the most accessible antecedent for adults and the local subject is the most accessible antecedent for children. A theoretical account is presented, which integrates reflexivity and the accessibility of the 3rd person object stressed pronoun in in BP.