Abstract: In DTN, the current routing forwarding strategies include flooding method based on copy and forwarding method based on knowledge. In order to deliver more messages with less knowledge oracle, a new routing algorithm which calculates the delivery predictability using the history contact information is proposed. The algorithm combines copy strategy and probabilistic routing. When one node meets the other node, a message is transferred to the other node if the delivery predictability to destination is higher at the other node. Binary mode copy strategy is used to distribute a message to a number of nodes to increase transmission rate and an active mechanism is used to delete redundancy messages. Simulation result shows this algorithm has a higher message delivery ratio than Epidemic, PRoPHET and BSW. In addition, this superiority scales better with the buffer size and the number of nodes.