On the purpose of improving efficiency of continuously variable transmission with reflux power,efficiency of previous system under low gear and reverse gear have been analyzed to optimize its structure based on analysis of speed modulation characteristic and transmission efficiency of transmission system.What's more,with maximum speed ratio,minimum speed ratio of transmission system and speed ratio of reverse gear having been calculated,design method of structural parameters has been brought out.Finally,SC7101 as reference,design on structural parameters of continuously variable transmission with reflux power has been presented on the base of performance of previous structure.