Parent-adolescent conflict can be intense, yet parents and adolescents do not always agree on the intensity of conflict. Conflict intensity tends to change during adolescence and is thought to be an indicator of how the parent-adolescent relationship transforms. However, parents and adolescents might differently perceive change in conflict intensity, resulting in changing discrepancies in conflict intensity throughout adolescence. Also, personality characteristics of parents and adolescents might affect the extent to which there are discrepancies in perceptions of conflict intensity. This multi-informant longitudinal study investigated a) the trajectories of parent-adolescent conflict intensity, b) the trajectories of informant discrepancies, and c) the prediction of these trajectories by parental and adolescent personality. Dutch adolescents (N = 497, 43.1% female, M age = 13.03 at T1), their mothers, and their fathers reported on parent-adolescent conflict intensity and personality for six years. Latent Growth Curve Modeling and Latent Congruence Modeling revealed curvilinear changes in conflict intensity, as well as in discrepancies thereof. Two cycles of discrepancies emerged. First, in early-to-middleadolescence discrepancies in perceptions of parents and adolescents increased, reflecting that adolescents' perceived conflict intensity increased. Second, in middle-to-late-adolescence, father-adolescent discrepancies increased further, reflecting that fathers' perceptions of conflict decreased. Resilient adolescents, mothers, and fathers reported lower levels of conflict intensity than Undercontrollers and Overcontrollers, but personality was not associated with the rate of change in conflict intensity. Finally, undercontrolling fathers and overcontrolling adolescents showed higher father-adolescent discrepancies. This study showed that parents and adolescents differentially perceive conflict intensity and that in the adolescent-father relationship, the extent of the differences depends on adolescent and father personality.