The invention belongs to the field of submarine topography synchronous positioning and mapping, and particularly relates to a self-adaptive underwater multi-beam synchronous positioning and mapping method. According to the invention, an AUV sounding data synchronous positioning and mapping technology based on particle filtering is achieved through adoption of an inverse distance weighting method to achieve data association under a condition that environmental features are not extracted and through adoption of Kurbeck-Labber divergence sampling to achieve particle number real-time adjustment. According to the method, data association under the condition that characteristics do not need to be extracted is achieved through matching of a particle sub-map and a mean value track sub-map, a particle number is controlled in real time through adoption of the Kurbeck-Leibull divergence, a particle weight is corrected through adoption of the terrain richness, and the robustness of the algorithm is improved. According to the method, characteristics do not need to be extracted from the submarine topography, the particle number can be controlled in real time, the mapping precision and real-timeperformance can be guaranteed, the applicability is good, the calculation overhead is small, and the real-time performance can be guaranteed.