AIM: Children and adolescents with bipolar parents have an elevated risk for anxiety disorders. However, antidepressant medications commonly used to treat symptoms of anxiety may accelerate the onset of mania in these already at-risk youth. Therefore, studies evaluating innovative non-pharmacologic treatments for anxiety in this population are urgently needed. METHODS: Subjects participated in 12 weekly sessions of mindfulness-based cognitive therapy for children (MBCT-C), a manualized group psychotherapeutic intervention utilizing cognitive behavioural principles and mindfulness exercises to increase regulation of attention and non-judgmental acceptance of present moment thoughts, emotions and experiences. Independent raters administered symptoms rating scales prior to each treatment session. Spearman correlations and paired-samples signed rank tests were used to examine outcomes. After-intervention surveys and session transcripts were reviewed to assess feasibility and acceptability of the intervention. RESULTS: Participants included 10 youth (meanage  = 13.2; 80% girls; 40% biracial) with generalized, social and/or separation anxiety disorders, and a parent with bipolar disorder. Clinician-rated anxiety was significantly reduced after intervention (meanbefore  = 11.1; meanafter  = 4.3; P < 0.01), as well as youth-rated trait anxiety (P = 0.03). Parent-rated emotion regulation significantly increased from before to after intervention (P = 0.05). Increases in mindfulness were associated with decreases in anxiety (P = 0.03). Finally, children and parents/guardians reported high levels of feasibility, acceptability and usefulness of the intervention. CONCLUSION: Findings support the feasibility, acceptability and preliminary efficacy of MBCT-C for treating anxiety in youth at risk for bipolar disorder. Future controlled and larger studies are needed to confirm these preliminary findings.