关键词: 蚁群算法, 多序列比对, 信息素

Abstract: In this paper，a multiple sequence alignment is presented based on improved ant colony algorithm.Some changes have done in the algorithm including the renewal mode of the pheromone，the select means of the characters，the search strategy of ants on the trip between ant nest and food，the random distributing of the ants beginning sequence.The results show that stagnation behavior of basic ant colony mutiple sequence alignment algorithm is avoided and a good ability of searching better solution in the last runs of the improved algorithm is achieved.

Key words: ant colony algorithm, multiple sequence alignment, pheromone