Corticotropin-releasing factor-binding protein regulates the availability of free corticotropin-releasing factor and is a functional candidate gene for affective disorders. The aim of this study was to examine the association between polymorphisms in CRF-BP gene and bipolar disorder in an isolated Swedish population. One hundred and eighty-two patients with bipolar I disorder and 333 controls from Northern Sweden were included in the study. Five single nucleotide polymorphisms and a deletion polymorphism in the CRF-BP gene were genotyped. The haplotype block structure of the gene was considered and the expectation maximization algorithm was adopted to estimate the haplotype frequencies. As a result, there were no significant associations of the different polymorphisms in the CRF-BP gene with bipolar disorder. In conclusion, this study in an isolated Swedish population does not support a role for the CRF-BP gene in the vulnerability for bipolar disorder.