Salinity depresses plant growth and final yield due to excessive toxic ions or their osmotic potential, resulting in physiological drought. This study focused on determining if plant- and animal-derived biostimulants (Aminolom Enzimatico®, İnori®, and Isabion®) improve plant growth, physiology, and stomata properties of the lower surface of leaves in broccoli under salinity. Broccoli seedlings were grown at the medium salinized with NaCl and control, and the biostimulants were applied to the soil (S), foliar (F), and S+F. Plant growth was inhibited by salinity, while the biostimulants enhanced the tolerance level to salinity. Stem diameter, plant fresh weight, and leaf area under salinity were improved by biostimulant applications, while S+F applications increased the fresh weight and leaf area under both saline and control. Electrolyte leakage precisely distinguished the differences between biostimulant applications. Among the biostimulants, İnori® effectively promoted morphological and physiological parameters, and there were also significant differences among the F, S, and F+S applications of the biostimulants. The F application was suitable for plant-derived biostimulants, while the S application of animal-derived biostimulant showed superiority. Therefore, plant-derived and animal-derived biostimulants should be applied on leaves and soil to reduce the hazardous effects of salinity in broccoli cultivation.