Genes which exhibit similar patterns are often functionally related. Microarray technology provides a unique tool to examine how a cells gene expression pattern chang es under various conditions. Analyzing and interpreting these gene expression data is a challenging task. Clustering is one of the useful and popular methods to extract useful patterns from these gene expression data. In this paper multi colony ant based clustering approach is proposed. The whole processing procedure is divided into two parts: The first is the construction of Minimum spanning tree from the gene expression data using MapReduce version of ant colony optimization techniques. The second part is clustering, which is done by cutting the costlier edges from the minimum spanning tree, followed by one step k - means clustering procedure. Applied to different file sizes of gene expression data over different number of processors, the proposed approach exhibits good scalability and accuracy