Background: Genetic interactions (GIs) refer to the phenomenon where the phenotype of one gene is affected by another one.Usually GIs are related with function.Epistatic miniarray profile (E-MAP) is a strategy to generate comprehensive and quantitative genetic-interaction maps.Several recent studies generating E-MAPs for different cellular functions raised insights with respect to biological networks at a systems level.Methods: Genes were deleted by homologous recombination of a linear DNA fragment carrying an antibiotic resistance marker (NAT or G418) flanked by homologous sequences to the targeted region.Crossing experiments were performed as 1536 format on a Singer RoToR machine.Colony sizes were measured from the digital images, and then were transformed into S-Score.Results: In this work, we constructed an E-MAP for budding yeast Saccharomyces cerevisiae and fission yeast Schizosaccharomyces pombe, generating ~220,000 and ~400,000 pairwise measurements separately.This high-density, quantitative genetic interaction map focused on various aspects of cell cycle network, including CDKs, DNA replication/repair, checkpoints machinery.We first showed overall conservation rate of the cell cycle network between these two yeast species is ~3% for positive interaction and ~8% for negative interaction.With stronger negative interactions, GIs tends to be more conserved.The conservation rate can be higher than 25% when S-score is lower than-16.Between functional modules, most of the significant GIs are conserved, but the individual GIs varied a lot (p>0.1).Conclusions: We show that stronger interactions tend to be more robust during evolution.The conservation is maintained on complex and module level.Besides, the individual GIs vary between conserved functional modules, which reveals that although the organization of functional modules or biology processes is relative conserved, genes interacted in these modules varied across organisms .