This paper proposes a UWB/LiDAR indoor positioning method based on improved beetle antennae search algorithm(IBAS) optimized particle filtering to address the issues of non-line-of-sight (NLOS) errorss in ultra-wideband (UWB) range and cumulative errors in LiDAR impacting positioning accuracy. In order to eliminate NLOS errors in the UWB measurement value, the method combines the benefits of high interference immunity and high temporal resolution of UWB with the high accuracy and efficiency of LDIAR. The distance between the combined positioning system and the UWB base station is solved using the LiDAR measurement information. The addition of the IBAS significantly reduces the number of particles needed by the algorithm, speeds up algorithm execution in real time, and successfully slows down the particle degradation issue. The global bit posture is then obtained by the graph optimization-based combination function of UWB/LiDAR. The experimental results show that the IBAS optimization algorithm only requires 20% particles of the original particle filtering algorithm for the same effect, and that when compared to single UWB and LiDAR localization, the localization accuracy of this proposed method is improved by 44.75% and 74.47%, respectively, with good results.