A sesquiterpene glycoside, cadin-2-en-1β-ol-1β-D-glucuronopyranoside (known as CR4-1), was isolated from Catharanthus roseus (Apocynaceae) hairy root cultures. C. roseus is widely used as an ornamental and medicinal plant and is cultivated mainly for its alkaloids. C. roseus has been reported to have pharmacologic properties such as anti-cancer, enzymatic anti-oxidant, and anti-diabetic effects. In this study, we demonstrated that CR4-1 significantly inhibited the in vitro invasion of MCF-7 human breast adenocarcinoma cells induced by 12-O-tetradecanoyl phorbol-13-acetate (TPA). Matrix metalloproteinases (MMPs) are known to be involved in cancer invasion and metastasis. Zymographic analysis showed that CR4-1 suppressed TPA-induced MMP-9 activity in a dose-dependent manner. We further demonstrated that CR4-1 suppressed the phosphorylation of extracellular signal-regulated protein kinase, but not p38 kinase or c-Jun N-terminal kinase (JNK). Moreover, CR4-1 attenuated TPA-induced degradation of κBα inhibitor (IκB-α). These results suggest that CR4-1 reduces the invasiveness of human cancer cells by suppressing MMP-9 expression through inhibition of the NF-κB signaling pathways.