Purpose: To evaluate the antifungal potency of Syzygium aromaticum (Dianthus) seed extract against the growth and aflatoxin production of Rhizopus stolonifer , and its immunomodulatory effect. Methods: Disc diffusion method was used for assay of antifungal effect of aqueous extract of Dianthus. Lymphoid cell counts, total and differential peritoneal exudate cell counts (PEC), phagocytic activity of PEC, and plaque-forming activities were determined. In addition, E-rosette-forming cells (RFC), T-cell mitogenesis cells and liver functions were measured. Results: The aqueous extract of Dianthus (50 %) exhibited high inhibition zone against most isolates of R. stolonifera . It produced significant increases in the number of splenocytes, as well as in the absolute number and relative proportion of macrophages ( p < 0.05). The extract also produced a gradual increase in the scavenging activity of PEC, and significant reduction in serum ALT, relative to control. Conclusion: These results suggest that Dianthus modifies biological responses by enhancement of the immune system, activation of phagocytosis, boosting of immune response, and prevention of liver damage. Keywords: Aflatoxin, Syzygium aromaticum , Rhizopus stolonifer , Lymphocytes, T-cells, B-cells, Macrophages