Misdiagnosis is common in bipolar disorder and disproportionally affects racial and ethnic minorities. There is interest in better understanding the contribution of differential symptomatic illness presentation to misdiagnosis.Utilizing the Genetic Association Information Network (GAIN) public database, this study compared clinical phenomenology between bipolar patients of African vs European ancestry (AA = 415 vs EA = 480). The Diagnostic Interview for Genetic Studies (DIGS) was utilized to evaluate symptom endorsement contributing to diagnostic confirmation of bipolar I disorder (BPI) and lifetime medication use.Elevated/euphoric mood was less endorsed in AA vs EA participants (p = 0.03). During the most severe episode of mania, AA participants, in comparison to EA participants, had a lower sum of manic symptoms (p = 0.006) and a higher rate of hallucinations (p = 0.01). During lifetime psychosis, AA participants, in comparison to EA participants, had a higher lifetime sum of delusions (p = 0.01) and hallucinations (p < 0.0001). AA participants reported lower use of lithium (p < 0.0001) and mood stabilizing anticonvulsants (p = 0.0003).The differential rate of manic and psychotic symptom endorsement from a semi-structured diagnostic interview may represent differential illness presentation based on biological differences or racial or study biases (e.g. ascertainment). Increased minority recruitment in bipolar research is therefore a necessary future direction.Recall and interviewer bias may affect study results, but are likely diminished by the alignment of symptom endorsement and medication use.