Bioassay-directed fractionation of the dried roots of Asparagus cochinchinensis led to the isolation of a new spirostanol saponin, asparacoside (1), two new C-27 spirosteroids, asparacosins A (2) and B (3), a new acetylenic derivative, 3' '-methoxyasparenydiol (4), and a new polyphenol, 3'-hydroxy-4'-methoxy-4'-dehydroxynyasol (6), as well as five known phenolic compounds, asparenydiol (5), nyasol (7), 3' '-methoxynyasol (8), 1,3-bis-di-p-hydroxyphenyl-4-penten-1-one (9), and trans-coniferyl alcohol (10). Compounds 1, 6, and 8 demonstrated moderate cytotoxicities in a panel comprised of KB, Col-2, LNCaP, Lu-1, and HUVEC cells, with IC(50) values ranging from 4 to 12 microg/mL. The structures were determined by spectroscopic and chemical methods.