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Introduction: One of the severe forms of affective disorders, defined in DSM-IV-TR, is bipolar disorder type1. This is a psychotic disease that coexists with structural and biochemical changes of CNS. It is probably under influence of environmental and/or genetic factors. Finger and hand prints are formed during the late first and second trimester of fetal development, and then remain unchanged. There are some suggestions that disturbance in dermatoglyphic patterns probably are in relation with appearance of bipolar disorder. It seems that this disturbance is appeared at the first and second trimester of fetal development, which is a critical period for CNS growth. This study is done to investigate the dermatoglyphic patterns in bipolar disorder. Materials and Methods: This is a case-control study in which we have studied the dermatoglyphic changes in 30 bipolar disorder patients and compared to those of 72 healthy controls. The χ2 test was used for quantitative and T-test for qualitative data analysis. Results: Results showed that TABRC in patients was decreased in comparison to healthy people but this decrease was not significant. Regarding the type of patients, fingerprints, Loop and Whorls forms were heterogenous and were significantly different in comparison to control group (p=0.001, p=0.003). Conclusion: It seems that dermatoglyphic patterns can be an interesting and probably suitable procedure in determining the prognosis of bipolar disorder type 1 and other psychiatric disorders.