The alkaloids of Glaucium fimbrilligerum Boiss. were first isolated by S. Yu. Yunusov and later by Slavik. Since one and the same plant may contain different alkaloids depending on its growth site and vegetation period, we investigated Glaucium fimbrilligerum collected in the vegetation period in the environs of Daraut-Kurgan (Pamir-Alai). Chloroform extraction showed it contained 0.62% (0.52% ethereal and 0.1% chloroform) alkaloids on dry plant weight. From ethereal alkaloids, sanguinarine sulfate and heleritrine were obtained; the mother liquor was separated into phenolic (0.09%) and nonphenolic (0.41%) fractions. Adding hydrobromic acid alcoholic solution to the nonphenolic fraction precipitated d-isocorydine hydrobromide (mp 224-225°C decomp.), and protopine/allocryptopine were isolated from the mother liquor. The phenolic fraction was chromatographed on alumina: benzene-methanol (99:1) yielded isocorydine/corydine, (96:4) yielded d-isoboldine and a base (mp 186-187°C, mol. wt. 317, UV maxima 242/293 nm, IR bands for methylenedioxy, aromatic ring, hydroxy group; diacetate mp 207-208°C), (7:3) yielded a base (mp 158-160°C) and corytuberine. We first isolated isocorydine, isoboldine, and corytuberine from this plant.