Background: Social cognitive neuroscience investigates the biological basis of social cognition. Bipolar Disorder (BD) is characterized by abnormalities in emotional processing and a classically relapsing-remitting course in which a patient’s mood may fluctuate between states of depression and mania. Recent studies have reported impairments on tests of face and facial emotion perception in BD but this body of literature is still somewhat limited. Brain derived neurotrophic factor´s (BDNF) single nucleotide peptide (SNP) Val66Met has been linked to worse cognitive performance in BD. Aim: To study the association of BDNF genotype and social cognition function in a sample of drug naive symptomatic young BD type I patients. Methods: 24 patients (SCID, DSM-IV) were submitted to Face and Emotion Expression Tests (FEEST), and genotyped for Val66Met SNP. Non parametric tests were used to compare performance between the genotypes groups. Results: Genotype Val66Met (40%) compared to Val66Val (60%) had a trend to worst performance in: recognition of disgust faces/Ekman 60 Test (p=0,056); Total points/Hexagonal test (p=0,06); recognition of anger faces/Hexagonal Test (p=0,074). Conclusion: Despite our small sample and the absence of Met66Met genotype it seems reasonable to assume that the cognitive deficit caused by the Met allele might also be found in social cognition. Keywords: facial expression, bipolar disorder, expressed emotion, BDNF.