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Antibiotics are one of the most important emerging contaminants as they have been detected in several environmental compartments including soil. Compared to the wide literature on the effects of antibiotics on aquatic organisms, knowledge and understanding of their potential effects on terrestrial environment is still scarce, especially when mixtures are taken into consideration. In this study, a screening-level phytotoxicity assay was used to evaluate the effects of three antibiotics (Oxytetracycline, Levofloxacin, Ampicillin) individually and in mixtures, on seed germination, root and shoot elongation of Egyptian clover (Trifolium alexandrinum L.) After five days exposure time, the acute effects of individual antibiotics and their binary and ternary mixtures were assessed using three endpoints, namely percentage of seed germination, shoot length and root elongation. The results of the study indicated that plant germination was insensitive to the individually tested antibiotics, with no significant decreases up to the highest treatment concentration of 100 mg L-1. Root elongation was observed as the most sensitive end point in individual antibiotics. However, increase in the root and shoot elongation was observed in mixtures relative to the individual antibiotics. The results show the importance of evaluating the toxicity of antibiotic mixtures, since they might have distinct effects when compared to the individual compounds.