Magnetic navigation algorithm is the key to geomagnetic aided navigation systems. At first, the basic principle of the magnetic matching algorithms is analyzed. On the basis of this, the research status and improving methods are summarized from four aspects of characteristic space, relativity measurement, search space and search strategy. The introducing of various new methods supplies some new ideas to modify the matching method. Finally, based on the problems appeared in engineering applications, the improvement strategies of the geomagnetic navigation algorithm are pointed out, which can be taken as a reference for the algorithm's engineering application.