The Libyan coasts provide a diverse environment with many seaweeds that are underutilized in agricultural development. The present study aimed to evaluate the effect of irrigation with seawater at concentrations (0, 10, 20, 30, and 40%) on the germination of wild and cultivated Ceratonia siliqua L. seeds and treatment by pre-soaking for 24 hours at a concentration of 10% of three species of seaweed extracts (Padina pavonica, Sargassum vulgare, Posidonia oceanica). The results showed that C. siliqua seeds were able to germinate under seawater irrigation levels up to 30% with a germination percentage of 18%. Salinity stress significantly decreased germination percentage, delayed mean germination time, and reduced radical lengths. The seeds treated with seaweed extracts showed improved performance and were able to tolerate salinity up to 40%. P. pavonica was observed as the most efficient in mitigating the adverse effects of salinity. The results showed no significant differences between wild and cultivated C. siliqua seeds for all studied traits. The study concluded that seaweeds could be used as a promising bio-stimulant in agricultural development fields.