Two new type Ⅱ ribosome-inactivating proteins (RIPs) were isolated from the mature seed of camphor tree (Cinnamomum camphora). They are named cinnamomin and cinphorin. The molecular mass of cinphorin A-chain is only half of cinnamomin A-chain, while their B-chains are the same. Their A-chains are RNA N-glycosidases, and the B-chains are lectins. The intrinsic cytotoxicity of type Ⅱ RIP is greatly dependent on the carbohydrate-binding activity and the specificity of its B-chain. The lectin activity of cinnamomin and cinphorin are investigated and compared with each other. They showed similar hemagglutination activity. Their saccharide binding specificities were studied by hapten inhibition, indicating that they were both galactose-specific. However, N-acetylgalactosamine failed to bind to the two RIPs as ricin/abrin did. The interactions of the two RIPs with specific saccharides were also investigated by fluorescence spectroscopy through which association constants were obtained. Their association constants of galactose or lactose were found to be identical.