Abstract In this research we focus on MLM companies in Taiwan area, interrelationship between each direct sales and how their own characteristics affect business. Our goal is to understand the uplink and downlink interrelationship in order to improve the their relationship in direct sales companies. This will promote the uplink to help downlink into fast development state and improve the business. As for MLM system, every direct sale does not have legal contract with MLM Company and every marketing unit act as an independent unit. On the other hand, every direct sales requires other units for support and makeup the whole MLM system. Therefore, the relationship between uplink and downlink is the base and strength element of MLM system. Researchers discover that direct sales joins in the MLM system is based on product requirement market more than open market or potential market. Therefore, all those direct sales need to take product requirement market into concern. If the product has large requirement market then it will be easier for the direct sales to expend their MLM system. For those people who did not join into direct sale their direct downlink will be their classmates and friends. In long term direct sales marketing, classmates and friends market are not enough, we need to walk out and open stranger market. In order to gain new market we need to continuously build up new relationship with all kind of people and only this will continuously expend the direct sales market. After direct sales join the MLM system, during the interaction with uplink it will go through initial state, enhance state, stable state and independent state four different states. Every single state will affect the relationship between uplink and downlink on how they build up, maintain and expend. During the direct sales time period we need to think of different tactics base on each state in order to achieve successful direct sales marketing. During each state when we are the uplink then we need to think how to lead the downlink into the whole system and make them become one of the whole system. In order to build up the long term relationship between direct sales and direct sales system is based on trust and mutually beneficial. In direct sales market the relationship between uplink and downlink makeup the base strength of the whole direct sales system. Therefore, enhance the relationship between the uplink and downlink is the key element in successful direct sales market. When direct sales are leading all the downlink they need to use admiration and inspirer as enhance elements. Let downlink learn, grow and independent and lead into road of success. Direct sales market mainly focus on ¡§duplicate¡¨. Therefore, uplinks pass all kind of successful ideas into downlinks and build up the strength base on the interaction between uplinks and downlinks. This is the truth strength behind the MLM.