Considering the increasing global population and demand for food, it is crucial to adopt agricultural practices that ensure both food security and environmental preservation. In this context, plant growth-promoting microorganisms (PGPM) and integrated crop-livestock-forestry systems (ICLF) have emerged as promising strategies for sustainable productive intensification. This research aimed to determine the effects of inoculating Azospirillum brasilense and Trichoderma asperellum on maize crops (Zea mays L.) grown in monocropping and ICLF systems. A complete randomized block design was performed in a 4 × 2 factorial arrangement with three replications. The crop systems included maize monocrop (C), crop-livestock (CL), crop-forest (CF), and crop-livestock-forest (CLF). Concomitantly, the co-inoculation (A. brasilense + T. asperellum) was compared to the control management (with no PGPM). CL and C systems with co-inoculation showed the highest yields, while the CF and CLF systems, which include the arboreal component, showed lower yields because of tree shading. CL + co-inoculation treatment was the most significant with increases of 17.14% in shoot dry mass, 43% in 1000-grain weight, and 9.56% in yield (t ha-1) compared to the C + control treatment. Additionally, the CL + co-inoculation treatment overcame the CLF + control by 136.63% in yield. Results indicate that the PGPM co-inoculation in maize within the CL system is an effective strategy for optimizing crop production.