E-commerce is becoming more popular on the Internet, smart cards have been used for safe transfers and transactions. Especially, business models using smart cards are actively being developed and the expense transaction method using smart card is becoming diverse since these various business models such as payment agent. So, in this paper, we propose the efficient mileage agent on the Internet, using smart card. This agent offers security for data and the simplicity of application development. Also, It is an independent program saved on Java Card and can calculate and save mileage, although the characteristic of the mileage is different from others through the calculating process of the Card.