Objective:To investigate the immunomodulatory effect of mixed konjac glucomannan(MKGM)on cyclophosphamide-induced immunosuppressed mice.Methods:The immunosuppressed mice model was established by cyclophosphamide.After treatment with MKGM for 25 d,organ index,lymphocyte proliferation,macrophage function,NK cell killing,and cytokine secretion of mice were observed.Results:Immunomodulatory effect of MKGM was firstly enhanced and then declined.Compared to model group,there were significant differences in organ index,lymphocyte proliferation,macrophage function,NK cell killing,and hemolysin in the medium-dose MKGM group(P＜0.01).HE staining showed that the low-dose MKGM had the best effect on repairing spleen injury caused by cyclophosphamide.However,medium-and high-dose MKGM had relatively weak immunomodulatory effects.Conclusion:The appropriate dose of MKGM can play an immunomodulatory role in the cyclophosphamide-induced immunosuppressed mice.