The current situation of single bucket excarator-truck loading and transporting system(LTS) both inside and outside China is reviewed and the concept of LTS number is proposed. For China's specially large-scale open pits, the LTS number for the time being should be more than 6-8 sets, depending on mine scale, mining engineering and equipment condition. Even when the proportion of equipment in good condition is greatly raised in the future, LTS number will be no less than 4 sets.