The present work was carried out with the aim to verify the interference of microorganisms associated to the seeds, in the electrophoretic patterns of proteins as zein, which are used in certification of genetic purity of corn cultivars. For this, seeds of the com cultivar (C-805), were infected with the fungi Aspergillus flavus, Fusarium nionilliforme and Penicillium spp., inoculated with the fungicides Benomil® and Thiabendazol and nontreated (T2). The seeds was incubated in chamber as (BOD) to 25 °C in the dark and 95% of humidits relative, for thirty days. For the evaluation of physiology, health quality and proteic patterns from zein, was taken samples to fifteen days (1st time) and to thirty days (2nd time). For electrophoresis analysis was used one witness (T1), that the seeds do not kept in chamber BOD, with aim to solve possibles effect from chamber. For eletrophoresis analysis the protein, was extrated of zein to the seeds with the buffers (12mM of sodic borat, pH 10, 1% of SDS and 2-β Mercaptaetanol to 2%). The results obtained allow to conclude that the proteic patterns from zein do not change for the fungi Aspergillus flavus, Fusarium monilliforme and Penicillium spp., when associated with seeds.