Through the result of the investigation on costumes in Bulgarian regions, the main factors for the formation of Bulgarian folk costume and its kinds and history have been found out so far as follows. For men, Bulgarian costume consists of a white shirt called Belodrenik, straight trousers and a waste band with checked or striped patterns or Tukanitsa to be worn on a long coat or a short jacket. In addition, men`s wear a black dress, Chernodrenik, which is a sort of sleeveless vest, on a shirt, the trousers, Potouri, whose upper part is loose and puffy are decorated with a black string and long felt boots or leather sandals for footwear. They also wear a black sheepskin hat or a flower-decorated and brimless felt hat. The main factors for the formation of Bulgarian folk costume have been under the influence of natural and environmental features and historical streams resulting from its geographical location. Bulgaria is agriculture-oriented society based on a continental climate. Accordingly, as for the classification of costumes, body-fit clothes, such as shirts and jackets which developed in Europe and fit the body shape, have featured in Bulgaria. Besides, Bulgaria was under the rule of Turk for a long time at the end of the Middle Age. Having been influenced a lot those days, its folk costume shows Turkish elements now. With geographical features, it was found that the southern area was influenced most by Turkey and Greece, and the types of folk costumes in Europe developed mainly from the northern area.