The essence of geomagnetic matching algorithm is digital map matching

and it can be solved by correlation matching algorithm.The principle of geomagnetic matching is presented and reason of disadvantage of conventional algorithm is analyzed.A novel algorithm is presented.Vectors in reference map which are less than the error according to sampling point are searched and composed sets respectively.Matching is started based on these sets.This algorithm can not only reduce matching-time but also depress the probability of mis-matching.Simulation experiment shows the algorithm has good robustness and can satisfy the need of embedded system much better than conventional algorithm.