Aster tataricus is a plant (family: Asteraceae) originated in the North-Eastern part of Asia. Its roots are well known in the Traditional Chinese and Japanese Medicine as herbal tea. The root extract possesses antibacterial, antiviral, antiulcer and diuretic activities caused by the different secondary metabolites. One class of these metabolites are astins – chlorinated, cyclic pentapeptides consisting of proteinogenic and non-proteinogenic amino acids – found in the early 1990s. Since then, over 15 different astins were discovered yet. Only a few of them show an anti-tumor activity which depends on the cyclic structure and the cis-dichlorinated proline. The concentration of astins is very low in root, only a few milligrams could be isolated from 10kg of dried roots. We isolated an endophytic fungus from the inflorescence axis of Aster tataricus which is capable to synthesize astins and might be an alternative as astin producer. We show the difference in the astin production in the fungus and in the plant along with the distribution of the fungus and the astins in the plant Aster tataricus.