Digital image correlation method (DIC) has higher requirement for search speed and measurement accuracy in displacement measurement. Some good algorithms in sub-pixel level measurement are difficult to take account of speed and accuracy. Therefore, a combinatorial DIC algorithm is proposed in this paper. It is based on an adaptive genetic algorithm to rapidly obtain the maximum correlation coefficient point at the sub-pixel level. Then,this point is used as a fitting window, and a sub-pixel displacement value is obtained by spline interpolation and quadric surface fitting. Taking the simulated speckle image as the research object, we analyze the measurement accuracy, measurement stability, and the search speed of the combinatorial DIC algorithm. The results show that the combinatorial DIC algorithm has obvious comprehensive advantages over a single algorithm in search speed, measurement accuracy, and measurement stability. It can meet the speed and accuracy requirements of DIC in sub-pixel micro displacement measurement.