Abstract: This paper proposed a novel distributed multi-hop collaborative localization algorithm(MCL) to effectively estimate the position of sensor nodes in sparse-anchored WSN.The scheme utilizes the collaborative communications with local multi-hop anchors to exclude alias position from possible estimated positions or minimize position area.We also investigate the factors of positioning accuracy and optimize selection of anchors based on error analysis to eliminate impact of redundancy anchors.We simulate the relationship between anchor density and positioning ratio and verify validity of our approach in Matlab.Simulation results demonstrate:(ⅰ) The algorithm improves the positioning ratio distinctly under low anchor density situation,specifically for nodes positioning on the margin of network.(ⅱ) The positioning accuracy is increased by anchor optimization and limit of error propagation.So it improved feasibility and decreased cost of WSN positioning techniques,significantly.