To mitigate the detrimental effects of salinity stress on vegetable crops, various approaches, including the applying of organic inputs during different growth stages, such as germination, are employed. This study, conducted in 2023, aimed to assess the influence of humic acid pretreatment on the germination characteristics and growth parameters of cucumber (Cucumis sativus) under salt stress. Two experiments, one in the laboratory and the other in a greenhouse, were carried out using a factorial design based on a completely randomized design with three replications. The experimental factors included humic acid priming at four concentrations (0, 50, 100, and 200 mg/l-1 ) and salinity at five levels (0, 25, 50, 100, and 150 mM NaCl). The results in the laboratory and greenhouse environment showed that humic acid exerted a positive impact on various germination and growth attributes of cucumber, including germination percentage, germination rate, seedling length, dry weight, vigor index, and chlorophyll a, b, and total under salt-stressed conditions compared to the control. In laboratory environment; the treatment with 200 mmol/l humic acid and no salt exhibited the highest germination rate (87%) and seedling length (12.66 cm). In greenhouse environment; the interaction between salinity and humic acid revealed that humic acid concentrations exceeding 100 mg/l1 could alleviate the adverse effects of salinity stress on total chlorophyll. However, at concentrations of 100 and 200 mg/l-1 humic acid, Salinity up to 50 mM could not reduce this trait. In conclusion, the cost-effective and easily applicable method of priming cucumber seeds with humic acid presents a potential strategy to mitigate the impacts of salinity stress in regions with saline water or soil.

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