The objective of the study was to evaluate the fermentation characteristics, losses, aerobic stability, and nutritive value of the silage of three cultivars of cactus pear {‘Orelha de Elefante Mexicana’ - OEM (Opuntia sp.), ‘IPA Sertânia’ and ‘Miúda’ [Nopalea cochenillifera (L.) Salm Dyck.]} mixed with three levels of inclusion of Leucaena [Leucaena leucocephala (Lam.) de Wit] hay (0, 15, and 30%). The design was completely randomized in a 3×3 factorial arrangement, corresponding to cactus pear varieties and Leucaena hay levels, with four replications. Gas and effluent losses, pH, organic acids, aerobic stability, and nutritional value of silages were evaluated. The silages of the cultivar OEM without the inclusion of Leucaena hay had a higher pH (4.95) compared to Miúda (4.11) and IPA Sertânia (4.17). The aerobic stability was maintained for more than 60h after opening the silos. The inclusion of Leucaena hay (up to 30%) increased the pH and reduced losses by effluents without compromising the fermentative characteristics of the silages, indicated by the predominance of lactic acid (93 g/kg).