Every country love to use their own currency and want to rise the price of their own currency in the international market. They never want any outside currency in which they have no regulatory control. Bitcoin is a such type currency because it is decentralized in nature. Bitcoin affects their country own currency value and ultimately affect their country economic and financial growth. Due to its digital nature it doesn't pay tax to the government. Bitcoin is also used as a crime tool for many anti social people. Because of this many country ban it in their country.