Abstract: In order to provide scientific basis for the selection of herbage suitable for under Eucalyptus plantation，variation of growth index（ height，branch and crown width） of Desmodium heterocarpon var. strigosum Meeuwen as well as soil nutrition content were investigated and analyzed before and after interplanting. The Eucalyptus forest under different stand ages of Sibao Forest Farm of Heshan city，Guangdong province was selected as the research base for interplanting of forest and grass. The result showed that the shade environment could restrain the growth of D. heterocarpon var. strigosum to some extent. In Eucalyptus forest of different ages，the herbage could grow all the year round，and there was no significant difference in their growth. Herbages grew well by the way of seed sowing method. Herbage planting could effectively restrain the growth of weeds by reducing planting spacing appropriately. The interplanting of herbage was good for the enhancement of the content of soil nutrients. Conclusion can be preliminarily drawn，it should be managed combining its growth characteristics，the interplanting under Eucalyptus can grow trend of the herbage is normal and improve the soil nutritional condition.