Objective To study the chemical components in Rabdosia excisoides.Methods The isolation and purification were carried out on silica gel column chromatography,the chemical structures were determind by physico-chemical properties and spectral analysis.Results Two compounds were isolated from R.excisoides and their structures were identified,one was named as excisoidesin A(Ⅰ),a new diterpenoid and the other was a known compound,oleanolic acid(Ⅱ).Conclusion Excisoidesin A is a new diterpenoid.