Abstract: In the absence of market demand information, the inherent properties of metamorphism, short life cycle and small residual value of fresh agricultural products bring great risk to retailers who sell fresh agricultural products. Retailers outsource procurement business to third-party logistics companies with close business relations therewith. It can not only transfer its procurement risk, but also make 3PL obtain certain business. Based on this, a game model between retailers and 3PL is established, to compare and analyze the influence of 3PL purchasing and retailer purchasing on the optimal decision and profit of retailer and 3PL as well as the profit of supply chain system under partial demand information. The results show that the judgment of the actual demand of 3PL on fresh agricultural products is more accurate when the forward direction demand risk is high. When the demand risk is small, the judgment of the actual demand of retailers on fresh agricultural products is more accurate. It is also found that in most cases, 3PL procurement is unfavorable to the supply chain system. Only when the forward direction demand risk is very high, or the consumption rate of fresh agricultural products is very large, or the loss sharing ratio is very high, can the 3PL procurement increase the profit of the supply chain system. However, the profit of 3PL is lower than that of retailer under the condition that the procurement increases the profit of supply chain system. It is suggested that retailers should adopt the method of returning 3PL profits to encourage 3PL to participate in purchasing management, so as to increase the profits of retailers, 3PL and supply chain system and improve the competitiveness of supply chain.

Key words: third party logistics, procurement outsourcing, partial information, fresh agricultural products