The pericarp of Cornus officinalis is well known famous medicinal drug in oriental countries. In this work, we have tried to evaluate the toxicity and also to find the lectin components from this seed. The lyophilized seed extract was lethal to experimental mouse at $250{sim}300mg/kg$ and this toxic components were related to proteins. The lectins components were partially purified from the extract by ion exchange column chromatography. These lectins were relatively stable at temperature variations and also stable at pH $4{sim}7$. The activity of these lectins did not inhibit by common carbohydrates molecules.