Small and medium-sized (SME) third-party logistics enterprises have a lot of problems such as a low degree of information which is the difficult problem of the logistics industry in China. In this paper, investigation is made into SME and 4PL both at home and abroad, and Web-based 4PL supply chain system model of Multi-TPLs is proposed. Different from the existing 4PL model, this model will chiefly serve TPL enterprises in the domestic trade, and solve more than 90% of problems of SME TPL information. All TPL enterprise resources will be managed in terms of 4PL, and maximum supply chain will be formed to ensure the independence of the internal management of TPL enterprises. All resources can be shared among TPL enterprises.