Included four Inbred lines of maize in a program of hybridization (full diallel crossing system) namely (1. W17-11, 2. N28, 3. AGR3 and 4. AGR11) On field of Voronezh in (2016, 2017). A comparison the objective was estimation of several genetic parameters for oil and protein content in maize. The genotypes was planted in Randomized complete block design with four replications. Significant differences were found among genotypes for oil and protein content. The results showed that the diallel hybrids (W17-11×N28), (AGR3×AGR11). Produced higher oil percentage (4.6%),while reciprocal hybrid (N28×W17-11) produced higher oil percentage (4.7%). The diallel hybrid (W17-11×AGR3) produced higher protein percentage (10.1%), while reciprocal hybrids (N28×W17-11), (AGR3×N28) produced higher protein percentage (9.6%). The higher positive hybrid vigour percentage for best parents for oil percentage (20.1%) for diallel hybrid (W17-11×N28) and (18.4)% for reciprocal hybrid (N28×W17-11). The higher positive hybrid vigour percentage for protein percentage (29.9%) for diallel hybrid (N28×AGR3) and (36.5%) for reciprocal hybrid (AGR3×W17-11). There is no significant in GCA and SCA for the other characters oil and protein. The average degree of dominance (a) was zero for diallel hybrids for oil and protein percentage. The average degree of dominance (a) for reciprocal hybrid was zero for protein percentage while more than one for oil percentage (1.5). The heritability percentage was low for broad and narrow sense for oil and protein percentage for diallel hybrids and reciprocal hybrids. Genetic variance dominance values 62D and genetic variance additive values 62A was low for characters for diallel hybrids and reciprocal hybrids. This research aims to study the effect of method full diallel cross increase in oil content and protein in the grain first-generation members of the F1 community maize. © 2020 Plant Archives. All rights reserved.