Background: Apiaceae family is one of the largest plant families with wide distribution all around the world. The genus Hippomarathrum has 28 species around the world which among them the species H. microcarpum outspread in the North, Northwest, West and Central of Iran, and also Turkey, Caucasus and Iraq. Objective: In this study, the main compounds in ethyl acetate extract from aerial parts of the plant Hippomarathrum microcarpum have been studied. Methods: The isolation and purification of the compounds were carried out using column chromatography. The structure of isolated compound established according 1H-NMR and 13C-NMR spectral data. Results: Two coumarins (osthole and isoimperatorin) and one sterol (β-sitosterol) have been isolated and identified from ethyl acetate extract. Conclusion: The presence of coumarines like osthole and isoimperatorin in H. microcarpum cause of the importance of this plant. This coumarines have verity of usages in traditional medicine and recent studies have supported most of these usages and revealed new effects of these coumarines. As regard that more research haven't been done about this plant and also because of significance effects of isolated coumarines, it seems necessary to perform further studies on biological effects of this plant.