The manner in which mothers engage in emotional discussion, or reminisce, with their young children about past emotional experiences poses important ramifications for child socioemotional and cognitive development. Maltreating mothers may have difficulty engaging in emotionally supportive reminiscing. The current study examined the role of maternal sensitive guidance during reminiscing as a process variable that may explain associations between child maltreatment and 3 child self-regulatory dimensions: lability/negativity, emotion regulation, and inhibitory control. Participants included 111 maltreating and 65 demographically matched, nonmaltreating mothers and their 3- to 6-year-old children (N = 176). The dyads participated in a joint reminiscing task about 4 past emotional shared experiences. Mothers reported on their children's emotion regulation and lability/negativity while children participated in a behavioral assessment of inhibitory control. Results indicated that maltreating mothers engaged in less sensitive guidance when reminiscing compared with nonmaltreating mothers. In the main analysis, maternal sensitive guidance mediated relations between maltreatment and child emotion regulation and inhibitory control, respectively, but not lability/negativity.