The purpose of this study was to identify differentially expressed genes and analyze biological processes related to leukemia. A meta-analysis was performed using the Rank Product package of Gene Expression Omnibus datasets for leukemia. Next, Gene Ontology-enrichment analysis and pathway analysis were performed using the Gene Ontology website and Kyoto Encyclopedia of Genes and Genomes. A protein-protein interaction network was constructed using the Cytoscape software. Using the Rank Product package for leukemia, we identified a total of 1294 differentially expressed genes, 357 of which were not involved in individual differentially expressed genes. Gene Ontology-enrichment analyses showed that these 357 genes were enriched in biological processes such as mRNA metabolism, RNA splicing, and mRNA processing. Pathway-enrichment analysis showed that the genes were involved in the intestinal immune network for IgA production, endocytosis, and the mitogen-activated protein kinase signaling pathway.