Answer:
U.S. Mint and BEP are two important unit of United States Department of the Treasury but they have a major difference.
The U.S. Mint is the unit of Department of the Treasury responsible for manufacturing coinage. It do not produce paper money. The Mint also produces coin products that includes bullion coins, commemorative coins, and medals which are used to control the trade and commerce.
Whereas The Bureau of Engraving and Printing (BEP) is the unit of U.S. Department of the Treasury that produces U.S. paper currency. It also produces engraved documents that includes security documents for government agencies and award certificates.
Hence, they are different parts of United States Department of the Treasury.