Abstract: Most existing researches on sensor networks consider networks where all sensors are static nodes or mobile nodes. To ensure good performance, sensor networks should have self-deploying and self-healing capability to handle coverage holes caused by random locations and sensor failures. However, a mobile sensor has much higher cost than a static sensor with similar sensing capability, and deploying only mobile sensors in the network can cause the sensor cost too high. To improve the coverage performance in a sensor network while keeping the sensor cost low, it is proposed to intentionally add many mobile sensors to a number of static sensors in a sensor network. Mobile sensors can improve network performance by moving to locations where there is a coverage hole. Thus, mobile sensors can essentially provide self-healing and self-optimizing capabilities in sensor networks. A hybrid sensor neuwork is composed of static nodes and mobile nodes. A novel mobile nodes deployment method based on virtual force among nodes is presented in order to deploy these mobile nodes for forming maximum coverage of sensing area. The effect forces resulted from virtual potential fields between these nodes are utilized to control the movement of mobile nodes. This way makes mobile nodes move to appropriate positions using a little energy consumed in allowable time. The feasibility of the algorithm is analyzed in theory. Its validity is verified by numeric simulation and the performances are compared with that of other three similar algorithms.