Abstract: The localization problem for robot exploring unknown environment is studied.Under some unknown environ-ments,it is difficult to extract natural landmarks reliably,and the data association problem often occurs.So a novel landmark system that can be configured based on localization requirements is proposed.The configurable landmark,landmark cast de-vice and landmark observation device are designed and implemented.When the robot exploring the unknown environment,it configures landmarks online and dynamically to assist localization and environment exploration.The configurable landmark is light,of low cost and energy saving,and so it is easy to be carried and configured dynamically.The proposed landmark system appears effective for unknown environment exploration in experiments.