To investigate impact of earthworms on growth and antioxidant enzyme system of three turfgrasses, Lolium perenne L., Festuca arundinacea L. and Poa pratensis L., we studied the effects of earthworms on biomass, malonaldehyde (MDA) content, as well as the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) of the turfgrasses grown in municipal solid waste (MSW) compost medium by adding earthworms into the MSW medium. Our results showed that addition of earthworms into the MSW medium increased the aboveground biomass of L. perenne and F. arundinacea by 3.53 and 12.17-fold, respectively. The same treatments enhanced the underground biomass of L. perenne and F. arundinacea by 127.45% and 148.94% respectively. By contrast, the aboveground biomass of P. pratensis was decreased by 42.37% when the earthworms were introduced into the MSW medium. MDA content in L. perenne and F. arundinacea was reduced by 51.30% and 87.52% with addition of earthworms into the MSW medium, respectively. An increase in MDA content in P. pratensis by 16.74 times was found by addition of earthworms into MSW medium. Furthermore, the presence of earthworms in the MSW medium had significant effects on antioxidant enzymes of the turfgrasses. Activities of SOD in L. perenne, F. arundinacea and P. pratensis were decreased by 64.93%, 13.38% and 83.56%, respectively. Activities of POD L. perenne, F. arundinacea and P. pratensis were increased by 41.15%, 5441% and 34.09%, respectively. Activities of CAT in L. perenne were increased by 5.61% with inclusion of earthworms in the MSW medium, whereas the same treatments led to decreases in CAT activities in F. arundinacea and P. pratensis by 11.73% and 33.23%, respectively. In conclusion, the present study demonstrates that earthworms in medium can markedly affect growth and the activities of antioxidant enzymes of turfgrasses, and that the effect is species-specific.