A preliminary germination trial determined that 5000 ppm NaCl is the threshold above which germination percentage and performance drop below 50% of control values as the maximum salinity tolerable for faba bean plants. Subsequently, two pot experiments were conducted during the winter seasons of 2020/21 and 2021/22 to assess the negative effects of 5000 ppm NaCl on the growth and physio-biochemical performance of faba bean plants, as well as the efficacy of OLE in mitigating these negative effects in NaCl-stressed plants. The results showed that salinity at 5000 ppm NaCl adversely affected faba bean growth, resulting in significant decreases in root system size, stem length, leaf and branch numbers, total leaf area, and the fresh and dry weights of roots, stems, and leaves. It also reduced concentrations of photosynthetic pigments, total carbohydrates, crude protein, and minerals (N, P, K, Ca, Mg), as well as the K⁺/Na⁺ ratio. Conversely, leaf area ratio (LAR), free amino acids, proline, polyphenols, and Na⁺ concentrations increased compared to control plants. Treating seeds with 0.1% and 0.2% ALE before NaCl stress exposure effectively mitigated salinity's negative effects, resulting in improved growth parameters, significantly increased levels of various bioconstituents and mineral nutrients, and reduced Na⁺ levels along with an enhanced K⁺/Na⁺ ratio compared to the control in both seasons, with 0.2% OLE being the most effective. This study recommends the application of 0.2% OLE as a strong biostimulant to enhance the growth and physiological performance of faba beans under stressful conditions.