In this paper the actual research status of ant colony system,which has in recent years aroused wide interests,is summarily reviewed.Several types of modified ant colony system algorithmare are briefly introduced,such as ant colony system (ACS),max-min ant system (MMAS),ant colony algorithm with mutation features,ant colony algorithm integrated with genetic algorithm and so on.And as examples,based on several applications in the power system,this paper investigates some situations combined with applications.Also some hardware realizations of ant as single agent are roughly brought forth.