Abstract: This paper reports the ecology and uses in Chinese folk medicine of 7 species of the Genus Cyclea (family Menispermaceae) grown in China.The occurrence of 10 isoquinoline alkaloids and the content of total alkaloids in the 7 species have been studied. The results showed that the plants bear close relations and contain similar Constituents. The present study affords useful data for the chemotaxomony of these plants.The contents of 1-curine and isochondrodrine in the roots and stems of these plants were determined by means of Dual Wavelength TLC Scanner, The results showed that these two alkaloids are present in comparatively large amounts in most species.The medicinal plants of Cyclea are valuable raw materials for the preparation of muscle relaxants.