Updated FTP location. Aflatoxin contamination caused by Aspergillus flavus in peanut is a serious constraint for food safety and human health. However, molecular mechanism/s underlying the defense response is poorly understood. A comparative proteomic analysis was carried out between two contrasting peanut genotypes, JL24 (WT-susceptible) and a near-isogenic transgenic event (OE-Def) in the same background expressing defensin gene (resistant) with different time points, To understand the proteome changes in OE-Def and WT control lines, a label-free quantitative proteomics analysis was performed at 0, 24, 40, 56 and 72 h after A. flavus inoculation using UPLC-ESI-MS/MS. Several resistance proteins in the secondary metabolic pathways related to phenylpropanoids, flavonoids, and fatty acid biosynthesis were strongly induced in the resistant genotype.