Business activities always generate large dataset and accumulate much larger dataset with many items in each transaction.According to the commercial character，frequent itemsets are classified into four classes：new，mature，aging，expired，and an incremental updating algorithm based on statistical information of classified frequent itemsets is put forward.The algorithm only scans newly increased transaction dataset twice without scanning original transaction dataset，and it can also classify all rules into four classes：new，mature，aging，expired with strong rule identification capability as well as higher rule identification efficiency.