The study aimed to determine the optimal ratio for the mixture of forage cactus and corn stover silage, emphasizing the evaluation of fermentative profile, microbial populations, dry matter losses, chemical composition, and aerobic stability. A completely randomized design with four treatments and five replications was employed in this study. Treatments included varying proportions of forage cactus in corn stover at ensiling (0%, 10%, 20%, and 40% of fresh matter). After a 100-day fermentation period, the assayed variables underwent regression analysis. Forage cactus inclusion led to linear dry matter and ether extract reductions, with crude protein showing a negative quadratic effect (p < 0.05). The pH and water-soluble carbohydrates exhibited negative quadratic effects with the increasing proportion of forage cactus (p < 0.05). Lactic and acetic acids exhibited quadratic effects, reaching their peaks at approximately 20% forage cactus (p < 0.05). Lactic acid bacteria demonstrated a linear decrease, while yeasts/molds displayed a negative quadratic effect (p < 0.05). Dry matter losses followed a quadratic pattern, with the minimum values observed at 20% forage cactus (p < 0.05). Additionally, the inclusion of forage cactus significantly enhanced aerobic stability (p < 0.05). The incorporation of 20% forage cactus into corn stover silage markedly improved its quality.