Wasps contribute to environmental quality and ecosystem services, and play a key role in the functioning of many environments. The present study identified the diversity of species of solitary wasps that occupied trap-nests in farming environments. as well as the architecture of the nests found. The study focused on three areas of agroecosystem, where 30 blocks of trap-nests, with four diameters (5 mm, 7 mm, 9 mm, and 11 mm), were installed. A total of 56 nests were occupied by solitary wasps, with the most frequent species being Trypoxylon sp.1 (N=100, 54.9%), Pachodynerus cf. brevithorax (N=31, 17.0%), Trypoxylon sp.2 (N=27, 14.8%) and Caenochrysis nigropolita (N=9, 4.9%). The wasps occupied preferentially the trap-nests of 5 mm and 7 mm in diameter. Six wasp families were recorded, with the most abundant being the Crabronidae with 127 individuals, followed by the family Vespidae (N=36). Reduced number of species was recorded in the study area with frequent use of pesticides, and farming practices, which may damage nesting sites. These findings provide important guidelines for the use of agricultural practices, and emphasize the need for the adoption of effective strategies for the conservation and sustainable management of the populations of these potentially beneficial insects. KEY-WORD: Conservation, hymenopterans, agroecosystems.