Abstract: Taking electrolytic manganese residue-phosphogypsum mixed matrix as the test material, adopting the method of planting ryegrass in the mixed matrix of electrolytic manganese residue and phosphogypsum with different cement contents, the effects of cement content on the growth and microbial diversity of ryegrass were studied, in order to provide reference for the application of electrolytic manganese residue-phosphogypsum mixed matrix to the ecological restoration of vegetation concrete.The results showed that the plant height and total biomass of ryegrass decreased with the increase of cement content, and decreased to 71.78% and 72.12% of the control respectively at 15% cement content.With the increase of cement content（3%-15%）,the chlorophyll content of ryegrass showed a trend of increasing and then decreasing, the content of MDA and the activities of antioxidant enzymes（SOD,CAT,POD） showed a trend of decreasing and then increasing, when the cement content exceeds 3%,the growth of ryegrass was inhibited.The addition of cement had no significant effect on the dominant flora at the phylum and genus level of the electrolytic manganese residue-phosphogypsum mixed matrix under the growth of ryegrass, but the relative abundance of Bacteroidetes increased by 70.71%-71.65% after the addition of cement.Ohtaekwangia abundance increased by 79.36%-165.50%.Considering the growth and microbial diversity of ryegrass comprehensively, the cement content in the electrolytic manganese residue-phosphogypsum mixed matrix should be no more than 3%,and ryegrass could be used as the electrolytic manganese residue-phosphogypsum mixed matrix to be used as an alternative plant for ecological restoration of vegetation concrete potential.