We have studied the alkaloids of the plant Corydalis marschalliana Pers. (family Papaveraceae) growing in Bulgaria, the alkaloid composition of which had not been studied previously. The dry plant (1 kg) was extracted with methanol, and the alkaloids were isolated from the evaporated methanolic solution using 2% hydrochloric acid. The acid solution was washed with ether, made alkaline with 25% ammonia, and then partitioned with ether and a benzene-butanol (3:1) mixture, yielding 0.56% combined ether-soluble alkaloids and 0.1% combined benzene-butanol-soluble alkaloids. Through methods including mixed melting point, IR spectroscopy, TLC, mass spectrometry, and comparison with authentic samples, we identified l-adlumidine, d-bicuculline, d-bulbocarpine, d-corydine, l-domesticine, protopine, and d-isoboldine. Additionally, three bases with melting points 192-193°C, 240-241°C, and 258-260°C were isolated but remained unidentified due to their small amounts.