Background: The genus Lomatopodium Fisch. & C.A.Mey., belongs to Apiaceae family and contains one herbaceous species growing wildly in Iran. There are only a few papers about the chemical constituents of these plants. Here, we focused on the isolation and identification of the main flavonoid glycosides and sterols from the aerial parts of L. staurophyllum, which has not been previously reported. Methods: Flowered aerial parts of the plant were dried and cut into small pieces, then extracted with ethyl acetate and methanol by percolation at room temperature. The separation process was carried out using several chromatographic methods. Structural elucidation was based on NMR and MS data, in comparison with those reported in the literature. Results: The isolated compounds from ethyl acetate and methanol extracts of L. staurophyllum were identified as nonanal (1), stigmasterol acetate (2), beta-sitosterol (3), quercetin 3-O-glucoside (4) and quercetin 3 – O - rhamnoglucoside (5) by comparison of their NMR spectral data with those reported in the literature. Conclusion: Ethyl acetate and methanol extracts of L. staurophyllum contain various flavonol glycosides and sterols as the main components. Pelargonic aldehyde (nonanal), a growth promoting factor in plant cells, is found to be occurred in this species and might be a cause of anti -diarrhea activity.