Abstract: Focus on the minutia matching algorithm which is important in automated fingerprint identification systems (AFIS). An improvement was made to the fingerprint alignment-based minutia matching algorithm. In the step of extracting minutia associated ridge information, ridge topologic information about bifurcation was extracted to use in the ridge alignment and minutia matching algorithm. The semi-changeable sized boundary box was used to make this algorithm robust to nonlinear deformation between fingerprint images. A new reference variable was introduced to compute and compare the similar degree of ridges; it can solve the problem of reference point pair selection with lower computational cost and faster convergent velocity of matching algorithm. Ridge alignment process and minutia matching algorithm were combined together, a simple and effective method was put forward in the alignment and matching algorithm. The experimental results show that the new method can greatly improve the matching speed and also develop the system-s performance with less resource engaged.