Introduction: : This investigation was carried out to analyze the central nervous system (CNS) depressant effect of the plant Cleome rutidosperma extract, after it was found to have been used by the local people in the Philippine for that purpose. ; Methods: : In this study presented below, the CNS depressant effects of the extract was evaluated in in vivo mice models; using the standard procedures of Open field, Hole cross and Thiopental sodium induced sleeping time tests. ; Results: : Using two test extracts at a concentration of 100 and 200 mg/kg, it was seen that the extracts showed significant (p