Artificial crosses were made between A. hypogaea, using lines of 'Tatu', 'Roxo', Tatuí x Roxo 80-1 and the cultivar Tatuí as female parents and introduced plants of items 30001 and 30005 reported as belonging to A. diogoi and of 30006 and 30035 of A. spp, under greenhouse conditions. From the pollinated flowers of A. hypogaea x A. diogoi, 53.4 and 45.2% gave rise to pegs and fruits with normal seeds, respectively. The amount of viable pollen grains ranged from 4.8 to 13.4 with an average of 8.3% in this cross compared to 97.2 and 95.7% observed for A. hypogaea and A. diogoi. In the crosses A. hypogaea x A. sp. 30006 and A. hypogaea x A. sp. 30035, 13 and 9 normal fruits with 22 and 15 viable seeds were obtained, respectively. The pollen viability varied from 3.5 to 15 with mean of 10% in the former cross and was around 9.9% in the latter, compared with 97.8 and 98.2% noted for A. sp. 30006 and for A. sp. 30035. These results showed that plants previously classified as A. diogoi belong to another species. They also demonstrated the possibilities of using A. diogoi, A. sp. 30006 and A. sp. 30035 in the peanut genetic improvement.