Multidimensinal assignment algorithm is an optimal data correlation algorithm. This paper studies the problem and proposes a new heuristic searching method-order searching algorithm. The new algorithm finds the elemet with minimum value according to the different order of the cost plane numbers under the feasible restraints to obtain the optimal solution in the global range. Furthermore, aiming at the disadvantage of the slowly processing in general detection scenario, this paper puts forward a modified algorithm-multilayer order searching algorithm. The new algorithms are easy to understand and achieve,and has theparallel characteristic. By the analyses of applications of the new algorithms and Lagrangian relaxation algorithm,the validity of the algorithms presented in this paper is verified.