Phytochemical investigation on the aerial parts of Corydalis impatiens (pall.) Fisch (Papaveraceae) resulted in the identification of four previous undescribed benzylisoquinoline alkaloids, impatienines A-D (1–4), together with 14 known analogues (5–18). The structures of these compounds were elucidated by extensive spectroscopic analysis (IR, HR-ESIMS, 1D- and 2D-NMR) as well as ECD calculations. All the compounds obtained were investigated for their inhibitory effect on the growth of A549, H1299 and HepG2 cancer cells. Compounds 7 and 15 exhibited pronounced inhibition against the A549 cancer cells with IC50 values of 6.81 μM and 3.17 μM, while the positive control cisplatin was 1.83 μM. Compounds 1–3 showed moderate inhibitory on the H1299 cancer cells. Compounds 4, 10–12, and 16 showed signiffcant activity against HepG2 cancer cells with IC50 values range of 4.41–8.75 μM. © 2023