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Greenhouse trials, intended to evaluate the resistance of sorghum genotypes to Rhopalosiphum maidis (Fitch), were conducted in a free choice test, at the National Corn and Sorghum Research Center of EMBRAPA, in Sete Lagoas, MG, Brazil. Seven Sorghum genotypes known as resistant to Schizaphis graminum (Rondani) and a commercial cultivar BRS303 were randomly sowed in a circular distribution with 5 centimeters between plants, in plastic pots with capacity of 5 kg. After emergence, the plants were covered with cylindrical cages, coated with “voil”. Eleven days after planting, 45 wingless aphids were released at the center of each pot. After 24, 48, 72 and 96 hours, the number of adult aphids per plant was recorded on each genotype. The number of nymphs on each plant was also recorded at the last evaluation. After that, the experiment was replicated with the absence of the genotype BRS303. In both trials, the experimental design was in randomized blocks, with split plots, allocating the genotypes in the plots and the insect exposed period in the subplots. The results obtained in the presence and absence of the genotype BRS303, the genotypes TX430 and TX430 (GR) were shown to be the less preferred to R. maidis. On the commercial hybrid BRS303 the greatest number of aphid was observed, followed by TX2567.