We investigated relations between 4- and 7-year-olds' (N=58) autobiographical memory and their use of self-regulatory private speech in a non-mnemonic context (a cognitive planning task). Children's use of self-regulatory private speech during the planning task was associated with longer autobiographical narratives which included specific rather than general memories and which were recalled with greater narrative cohesion and more evaluative information. Children's use of private speech that served no regulatory function was unrelated to all memory variables. The relations between self-regulatory private speech and autobiographical memory were independent of children's age, general verbal ability, and gender. Our findings are discussed in the context of the social interaction perspective on autobiographical memory development. (Contains 3 tables.)