With E-commerce's development, E-mail has become a prevailing channel of communication in Internet. The interaction amount of customers' usage will increase massively and whether a call-center deals with them effectively and efficiently will directly influence customers' loyalty to the company. Via E-mail Auto Reply System of Neuro Linguistic Programming, the system can automatically analyze content of words. If the system can fully recognize the content of an E-mail, it will automatically reply to customers. If an E-mail needs to be handled by the call-center, the system will provide an agent the customer's related information in advance for consecutive customer service. E-mail Auto Reply System not only directly reduces personnel cost but increases customer representative's capacity to handle E-mails. Ultimately, it will improve our service quality and then increase our customer's satisfaction.