Aspergillus flavus is a pathogen of corn, peanut, and other crops which produces carcinogenic mycotoxins known as aflatoxins. Previous studies have shown that drought stress results in exacerbated aflatoxin production. Drought-associated oxidative stress caused by reactive oxygen species (ROS) is suspected to contribute to increased aflatoxin production during infection. Here, the responses of field isolates of A. flavus with varying degrees of aflatoxin production capability to H2O2-derived oxidative stress were examined using iTRAQ proteomics. Three isolates: AF13 (highly toxigenic), NRRL3357 (moderately toxigenic), and K54A (atoxigenic), were cultures in aflatoxin conducive yeast extract-sucrose (YES) medium amended with 0, 10, or 20/25mM of H2O2. Identified differentially expressed proteins were used for functional prediction, cellular localization, and pathway analyses to identify molecular mechanisms involved in A. flavus oxidative stress responses relative to aflatoxin production capability. Correlative analyses with previously obtained transcriptome data for the same isolates under the same experimental conditions was also performed with a low degree of correlation (r = 0.1114) observed between the protein and transcript data suggesting possible post-transcriptional regulation of oxidative stress responses. The identified stress responsive mechanisms provide a basis of investigating novel approaches of enhancing host resistance against aflatoxin contamination.