In general, the goal of data mining is to extract knowledge from data. Data mining is an inter-disciplinary field, whose core is at the intersection of machine learning, statistics and databases. There are several data mining tasks, including classification, regression, clustering, dependence modeling, etc. Based on the deep research of ant colony algorithm, an ant colony decision rule algorithm is proposed for rules mining based on the thought of ant colony and rule mining of decision tree. Then the algorithm is compared with C4.5 and applied on the rules mining and the results are showed by simulation.