Designing accurate localization algorithms is a research focus in WSNs (Wireless Sensor Networks). Aiming at the problem that the large estimated distance error between nodes could result in inaccurate localization in Distance Vector-Hop (DV-Hop)

we proposed an improved three-dimensional DV-Hop algorithm with continuous hop value in this paper. Firstly

the algorithm explored the relationship between the distance of neighbor nodes and the volume of intersecting spheres which is composed of the corresponding node locations and communication radius. In addition

the definition and parameter modification calculation formula of continuous hop value were put forward. Then we explored the influence of network environment on parameters and determined parameters value through simulation. The accurate continuous hop value was used instead of the hop in DV-Hop to reduce the estimated distance error between nodes. The simulation results show that the algorithm effectively reduces the localization error without increasing the complexity of the algorithm and additional hardware.