The effects of warning on false recognition and associated subjective experience of false recollection and familiarity were investigated in 7-to 13-year-old children and young adults (N = 259) using the Deese-Roediger-McDermott (DRM) paradigm. Two warning conditions (warning with an example of a critical lure and warning without an example of a critical lure) were compared to a control condition, in which no warning was received. We found that 7-to 8-year-olds exhibited higher false recognition in the warning-with-example condition compared with the control condition; in contrast, 12-to 13-year-olds and young adults exhibited reduced false recognition in the warning-with-example condition. No effect of warning was observed in 10-to 11-year-olds. The subjective experience associated with false memories was similar across ages. In contrast, age-related increases in subjective recollection were found for true memories. The processes that enhance or suppress false memories during development are discussed.