The effectiveness of exogenously applied zearalenone (ZEN) in alleviating water deficiency stress of pea (Pisum sativum L.) and yellow lupine (Lupinus luteus L.) was analyzed in the pot experiment. ZEN was applied in the form of spraying in the flowering phase on the first day of induced drought. The effectiveness of ZEN was evaluated based on physiological (electrolyte leakage, greenness, and photosystem II activity) and biochemical (protein, proline, ascorbic acid contents, and antioxidant enzyme activity) parameters after 14 days of drought. The yield and yield quality defined as yield components, total protein, fats, sugars, and antioxidants (tocopherols and β-carotene) were measured in newly formed seeds. ZEN residue in the seeds was analyzed employing UHPLC-MS/MS to exclude its accumulation. The results showed the possibility of reducing the effects of drought stress through the use of ZEN. It was manifested by increased cell membranes stability and antioxidant enzyme activity and above all ZEN increased crop yield, compared to untreated plants. ZEN modified seed composition by inducing the accumulation of fats and antioxidants. There was no accumulation of exogenous ZEN in seeds.