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• Exogenous application of H 2 O 2 and H 2 S alleviated the adverse effects of salt stress. • Application of H 2 O 2 and H 2 S increased N and K while reducing Na content. • Spraying of H 2 O 2 and H 2 S increased yield and yield components of stressed plants. • Plants sprayed with H 2 O 2 showed the highest SOD, POX, and CAT activities, while plants sprayed with H 2 S showed the highest APX activity. • Chlorophyll (a and b) and carotenoids increased significantly in plants sprayed with H 2 S compared to those sprayed with H 2 O 2. Salt stress is one of the most damaging abiotic stresses and is likely to worsen in arid and semi-arid regions under climate change, limiting plant production and reducing crop yields. This study was conducted in an open field in the desert under a saline environment, saline soil (9.68 dS.m−1) and saline irrigation water (7.12 dS.m−1), to evaluate the protective effects of H 2 O 2 and H 2 S on broccoli, two levels of H 2 O 2 (1, and 2 mmol. L−1), and two levels of sodium hydrosulfide (NaHS), H 2 S donor (0.1 and 0.2 mmol. L−1). Foliar application of either H 2 O 2 or H 2 S was effective in mitigating the adverse effects of salt stress on growth and yield of broccoli. Chlorophyll (a and b), carotenoids, and APX were significantly increased in plants sprayed with H 2 S compared to those sprayed with H 2 O 2 , while SOD, POX, and CAT activities were greater in plants sprayed with H 2 O 2. The largest decrease in malondialdehyde (MDA), H 2 O 2 , and Na accumulation was observed in plants treated with 0.2 mmol. L−1 H 2 S. Broccoli yield, nutritional content, and cell membrane stability index (CMSI) were increased with foliar treatments, all foliar treatments yielded larger and heavier broccoli heads than untreated plants. However, plants sprayed with 0.2 mmol. L−1 H 2 S showed the most promising results, significantly enhancing broccoli yield parameters in terms of head fresh weight (24.5%), head dry weight (19.2%), and head diameter (17.7%), and nutritional content such as vitamin C (16.8%) and total soluble solids (9.9%), as well as, leaf nutrient content in terms of N (21.2%) and K (15.6%), with decreasing sodium content by 20.3%. The results suggest that foliar spraying of H 2 O 2 and H 2 S could be an effective physiological method to mitigate abiotic stress and improve plant growth and yield. [Display omitted] [ABSTRACT FROM AUTHOR]