Efficient frequent pattern mining algorithms are decisive for mining association rule. In this paper, the authors examine the matter of association rule mining for items in a massive database of sales transactions. Finding large patterns from database transactions has been suggested in many algorithms like Apriori, DHP, ECLAT, FP growth, etc. But here, they have introduced newer algorithm called Improved Frequent Pattern Mining Algorithm with Indexing (IFPMAI), which is efficient for mining frequent patterns. IFPMAI uses subsume indexes i.e. those item sets that co-occurrence with representative item can be identified quickly and directly using simple and quickest method.