Human Angiogenin (hAng) is a member of the ribonuclease A superfamily and a potent inducer of neovascularization. Herein, protein interactions of hAng in the nucleus and cytoplasm of the human umbilical vein cell line EA.hy926, have been investigated by mass spectroscopy. The first gel-free analysis of hAng immunoprecipitates from the cytoplasmic and nuclear extracts from EA.hy926 cancer human cell line, revealed many statistically significant potential hAng-interacting proteins. The majority of the proteins identified by the mass spectrometry analysis are parts of multiprotein complexes, and some of them are common in nucleus and cytoplasm, including spliceosome, proteasome, and molecular chaperone TRiC/CCT. These complexes are involved in crucial biological pathways, implicating thus the key role of hAng in many vital cellular processes.