Objective: To examine the bidirectional relationship between parent-child discord and treatment outcome for adolescent treatment-resistant depression. Method: Depressed youth who had not responded to an adequate course of a selective serotonin reuptake inhibitor (SSRI) were randomized to either a switch to another SSRI or venlafaxine, with or without the addition of cognitive behavior therapy (CBT) in the Treatment of SSRI-Resistant Depression in Adolescents (TORDIA) study. The Conflict Behavior Questionnaire was used to assess adolescent (CBQ-A) and parent-reported (CBQ-P) parent-child discord. The impact of remission on parent-child conflict, and the differential impact of medication and CBT on the CBQ-A and CBQ-P, were assessed using generalized linear models. Results: Although there were no differential treatment effects on parent or adolescent-report of conflict, remission was associated with improvement in the CBQ-P. In general, intake family conflict did not predict remission, except in the sub-group of participants whose parents reported clinically significant parent-child conflict at intake, for whom high levels of parent-reported conflict predicted a lower likelihood of remission. Conflict also did not moderate treatment response. Conclusions: Remission of depression may be sufficient to reduce parent-reported parent-child conflict. However, higher parent-reported conflict, in the clinically significant range, predicts a lower likelihood of remission from depression. Clinical trial registration information--Treatment of SSRI-Resistant Depression in Adolescents (TORDIA); http://clinicaltrials.gov/; NCT00018902. (Contains 2 figures and 2 tables.)