Abstract: In order to study the value of information sharing, this paper considers a dualchannel supply chain that consists of one manufacturer and one retailer. The retailer holds his private information about his own valueadded cost in this supply chain system. The supply chain is modeled as a Stackelberg game. The impact of information sharing on the manufacturer and retailer’s equilibrium strategies and profits were analyzed and the value of information sharing to both the manufacturer and the retailer was investigated. It is found that the value of information sharing on the manufacturer is always positive, but this is not right for the retailer.