A new coumarinolignan glucoside named yinxiancaoside C, along with five known benzofuran lignans, have been isolated from the whole plant of Chloranthus japonicus Sieb. The structures of compounds 1-6 were elucidated by chemical and spectroscopic methods including 1DNMR, 2D-NMR, ESI-MS and HR-ESI-MS. Five known benzofuran lignans were firstly discovered in the Chloranthaceae. In addition, the cytotoxic activity of the isolated compounds against human hepatoma (Hepg-2), ovarian carcinoma (OV420), and breast cancer (MCF-7) cells was investigated by MTT method.