Polyploids are characterized by various morphological, physiological and biochemical changes. The aim of the research was to evaluate corn tetraploid forms obtained from different maize hybrids of local origin compared to diploids, after some reproductive and biochemical indices, in order to widen genetic variability and exploitation in the breeding process. The research was carried out at the Department of Plant Biology of the State Agrarian University of Moldova in the years 2016-2017. The experimental lot was placed on the experimental sector of the Faculty of Agronomy. As biological material served diploid and tetraploid maize populations from 9 hybrids originated in the Institute of Crop Production"Porumbeni". The analysis of maize tetraploid ears revealed that the genotype had a greater influence then poliploidy level in the determination of the studied paculiarities. Some parameters (diameter of the rachis, mass 100 grains) are more prone to genomic changes. In the tetraploid grains obtained were found a higher content (% s.u.) of proteins, lysine, lipids; a lower level of starch and ash, an irrelevant difference in cellulose content. The specific influence of genotype is highlighted in the determination of these indicators.