Research on adolescent emotion has generally focused on expressions of emotion; however, there are reasons to believe that adolescents' experiences of emotion may be related to adolescent development in unique and important ways. This study examined the relation of adolescents' emotional experiences of conflict with their mothers to their internalizing and externalizing symptoms at three time points, each a year apart. After participating in videotaped conflict negotiation tasks with their mothers, adolescents (N=80) watched the videotape of their interactions and used a joystick to make continuous ratings of how negative, positive, or neutral they felt during the discussions. Hierarchical Linear Modeling was used to assess relations among their continuous emotion ratings and their internalizing and externalizing symptoms 1 year before the interaction task, at the time of the interaction task, and 1 year later. Adolescents' externalizing symptoms at the time of the conflict task were associated with negative emotion that decreased across the conflict discussion. Relations between emotional experience and internalizing symptoms a year later were moderated by adolescent gender, revealing that a tolerance for increasing negative emotion predicts fewer future internalizing symptoms for girls. The importance of adolescents' ability to tolerate negative emotion during normal developmental conflicts is discussed.