Abstract: According to the characteristic of Distributed Intelligent Question Answer System (IQASD), the paper afford intelligent classify algorithm of distributing ant colony based on the study of ant colony optimization for classify rule discovery, analyzing and testing the algorithm's application in case base's data mining of IQASD.Practices prove that the algorithm can mining data of IQASD's case base in effect, make IQASD's searching more efficiency and intelligently, promote IQASD's application enter a new step.