This report deals with the existence of epidemiological, clinical and evolutional particularities in bipolar disorder relating to cultures and to geography underlined in the literature. The objective of this work was to analyse bipolar trouble by descriptive and comparative profiles of two samples belonging to French and Tunisian cultures and to discuss the differences based on epidemiological, clinical, therapeutic and environmental parameters. We have carried out a descriptive and comparative retrospective study among 45 bipolar I in-patients including 30 Tunisian and 15 French subjects. Our study brings to evidence trans-cultural differences in the expression and evolution of bipolar trouble, these differences reflect the impact of environmental factors.