The purpose of this study was to compare the two types of selection methods known as BLUP and individual selection (IS) in populations of rustic chicken, evaluating the trait of slaughter weight and considering the averages of genetic gain and phenotypic value as response variables. A population of rustic chicken was simulated in the program Genesys, considering the basal population with 500 males and 500 females, from which was randomly chosen 120 males and 240 females. Then, the selected population was simulated considering the sexual ratios of 3, 4, 5 e 6 females per male in two selection types: Individual Selection (IS) and BLUP. In each selection method, the random mating system between breed chickens was used. Selection was performed during 15 consecutive and non-overlapping generations, with 10 simulation repetitions per generation, in order to decrease the genetic oscillation effects. The average genetic gain and the average phenotypic value in all methods and mating systems were evaluated. The results show that the ratio 6:1 was superior to the other sexual ratios in the two types of selection. When comparing the two selection systems, IS was superior to BLUP for the high phenotypic value of slaughter weight. Thus, the sexual ratio of six females for each male is recommended for individual 130 Colloquium Agrariae, vol. 13, n. Especial 2, Jan–Jun, 2017, p. 129-134. ISSN: 1809-8215. DOI: 10.5747/ca.2017.v13.nesp2.000218 selection, with which will allow high phenotypic values, with lower need of males