In this work, Chinese hamster ovary (CHO) cells were used to examine the protective effects of glycyrrhizic acid (GA) on the reproductive toxicity of heavy metal ions, including Cd 2+ and Cu 2+ . As a result, both metal ions induced significant toxicity in CHO cells after 48-h treatment, as revealed by a severe decrease in cell viability. GA and glutathione (GSH) largely reduced the toxicity caused by Cd 2+ and Cu 2+ , which could be due to their recovery of GSH levels and superoxide dismutase (SOD) activities in CHO cells. In addition, GA and GSH significantly up-regulated the gene expressions of glutathione S-transferase (gst), sod, and heme oxygenase (ho)-1, which could be another explanation for their protective effects. More importantly, GA exhibited comparable protective effects as GSH but at much lower concentrations (50-100 µM v.s. 500-1000 µM). Therefore, GA could be effective for the alleviation of reproductive toxicity of Cd 2+ /Cu 2+ , which needs further investigation in animal models.