Business English correspondence can effectively deliver and store information. Although the two parties of trade can communicate through verbal means, for international business trade, oral communication due to the limit of time and space, is far time-consuming than written communication. The oral transmission of information while fresh and instant, but this fresh and instant will disappear with the passage of time. Business English letters as a black and white of the written material, in a certain extent can be regarded as an agreement or contract, to the provisions of the trade between the two sides of their respective rights and obligations. In international business cooperation, the business English correspondence is sent out, it has the nature of the legal documents that can be used as the basis for business credentials, can also be prepared in the future to see. Therefore, business English correspondence is one of the most important tools for the communication between the two parties to maintain close contact with each other, and every stage of the business activities can not be separated from the media. 

Business English correspondence is an important means to establish the image, establish and maintain business relationship between the two parties. As is known to all, the company attaches great importance to its in business reputation and image, and these not only rely on product quality and other hardware facilities can guarantee, but also rely on the business letters as a message of friendship, to display the image of the "software". A proper and appropriate business letter will undoubtedly leave a deep and good impression on each other, which is essential to the long-term development of the enterprise and the long-term trade relationship with its partners.