Episodic future thinking (EFT), the ability to imagine experiencing a future event, and prospective memory (PM), the ability to remember and carry out a planned action, are core aspects of future-oriented cognition that have individually been the focus of research attention in the developmental literature. However, the relationship between EFT and PM, including the extent to which it varies with PM task type, remains poorly delineated, particularly in middle childhood. The current study tested this relationship in 62 typically developing children aged 8-12 years. Results indicated that EFT ability was significantly related to performance on three types of PM tasks (regular and irregular event based and regular time based). Age was not found to moderate the relationship. Children's performance on the retrospective memory component of the PM tasks mediated the relationship between EFT ability and their performance on three types of PM tasks. For irregular event-based tasks, however, EFT made an additional significant contribution. This study adds to the limited empirical literature supporting a relationship between EFT and PM in this age band and supports theoretical models arguing that EFT ability may support PM performance by strengthening the encoding of PM task details in retrospective memory. However, additional mechanisms were also indicated for irregular event-based PM tasks, possibly involving strengthening of cue-context associations. These data show for the first time that the contribution of EFT to children's PM performance varies across task types. This study provides an important and novel contribution to current understanding of the processes that underlie PM development