Drought is a major constraint to agricultural productivity, necessitating effective mitigation strategies. This study investigates the effects of steel slag (S) and green waste compost (OA) on enhancing durum wheat (Triticum durum) resilience to water scarcity under open-field conditions across two growing seasons. Five treatments were tested: Control, recommended NPK, steel slag (S) at 0.7 T ha(-)1, green waste compost (OA) at 4.0 T ha(-)1, and a combination of steel slag and green waste compost (S_OA), under well-watered (100% ETc) and drought stress conditions (30% ETc). Results indicated that durum wheat plants treated with a combination of steel slag and compost (S_OA) demonstrated improved drought tolerance, with photosynthetic efficiency increasing by 5.13% in 2023 (S1) and 4.78% in 2024 (S2) in comparison to control. Antioxidant enzyme activity was significantly improved, with catalase (CAT), peroxidase (POX), and polyphenol oxidase (PPO) increasing by 80%, 51%, and 48% in S1, and 68%, 51%, and 31% in S2, respectively, compared to the control. Leaf relative water content (RWC) was enhanced by 24% in S1 and 27% in S2. Additionally, S_OA-treated plants showed higher grain yield under drought stress, with increases of 68% in S1 and 59% in S2, while grain protein content improved by 51% in S1 and 42% in S2, and grain nitrogen content increased by 35% in both years compared to untreated plants. These findings suggest that the co-application of steel slag and green waste compost is an effective strategy for improving drought tolerance, yield, and grain quality in durum wheat, offering a sustainable and cost-effective solution for arid and semi-arid regions.