Abstract: In order to solve the optimal test link problem when testing embedded instruments in reconfigurable scanning network, a method based on ACO algorithm is proposed. Firstly, the overall elements in the scanning network are abstracted into a node network structure that can be recognized by the computer. Secondly, aiming at the loop problem in the network, an "active" tabu table is proposed to release the node data in the tabu table when the designated-test-point is searched, so that the searched nodes can be searched again. Finally, in order to make the optimal test link better searched, the pheromone coefficient change factor is introduced to combine the pheromone update with the network scale to reduce the pheromone update range, so as to avoid falling into local optimization due to excessive enhancement of pheromone concentration in the later stage of search. Meanwhile, the adaptive pheromone volatilization coefficient is adopted to ensure the convergence rate of the algorithm and improve the global search ability. The simulation results show that the algorithm can effectively solve the optimal test link of the designated-test-point s in the reconfigurable scanning network. And compared with the basic ACO algorithm, it has higher search efficiency, practicability and applicability.