A new Cephalotaxus alkaloid, namely Cephalounei A (1), was isolated from the stems of Cephalotaxus fortune Hook. f. Their structures were elucidated by spectroscopic and mass-spectrometric analyses, including 1D-, 2D-NMR and HRESIMS. The relative and absolute stereochemistry of 1 was determined by a combination of NOESY correlations and electronic circular dichroism (ECD) spectra, respectively. The cytotoxicity of all compounds were evaluated against five cancer cell lines.