In this paper, a system data sharing algorithm is proposed to make WSN nodes build up dynamic multi-hop network. So it is also called dynamic multi-hop data sharing algorithm (DMDS). Compared with the algorithm based on mobile ad hoc proposed by MANET working team, it is more suitable to wireless sensor network (WSN) in many aspects. It adopts time flooding broadcast to make each node be able to realize data exchange with the whole system. In addition, it has the following characteristic: small computing cost because of no need of dynamic router table and each node can take on data transmission, so it can solve hot spot problem to some extent. Therefore it is a valuable solution for simple WSN nodes to build up a dynamic multi-hop network. A time delay experiment is also available to analyze the performance of it.