Abstract:The fruits,pollen grains,vascular bundles.stomata and endosperm cells of 4 Cnidium species werestudied and determined by stereological method and computer image analysis technique. Statistical data were presen-ted.In the volume of fruit and the area of vascular bundle,Cnidium dahuricum is the biggest,then C.salinum,Cjaponicum and C.monnicri successively.In the volume of pollen grain,C.salinum is the biggest,followed by C.dahuricum,C.japomicum and C.monnieri in soccession In the volume of endosperm cell,C.dahuricm is alro thebiggest,and then C.japonicum,C.salinum and C.monnieri in order.