Background: Achyranthes aspera Linn., known as Chirchira (Hindi), Agadha (Marathi) is an indigenous herb found in India. The herb has been reported to have variety of activities like antifertility,  antihyperlipidemic, antidiabetic, immunomodulatory,  anticarcinogenic, diuretic and  cardiotonic, analgesic,  anti-inflammatory, hypnotic, antifungal and antibacterial  activity. It has been also reported to have central anti-nociceptive activity in thermal induced pain methods in our earlier studies. We wanted to study its neuropharmacological effects, which may throw light on understanding the underlying mechanism for its central activity. Purpose: The present study was designed to evaluate CNS depressant and behavioral effects of A. Aspera extract and to study the phytochemical responsible for these activities with possible mode of action. Methods: The effects on behavioral activity was studied using open field test (OFT). The extract was given intraperitoneally at a dose of 400 mg/kg. Diazepam (2mg/kg body weight i.p.) was used as standard. Data was analyzed by ANOVA test followed by Dunnett’s test. All the results were expressed as Mean (±SEM). P less than 0.05 was considered significant. Results: Phytochemical screening revealed presence of triterpenoids, saponins, alkaloids (betaine, achyranthine) and steroids as major constituents. The result of the study demonstrated that ethanol extract of A. Aspera (400 mg/kg i.p.) decreased locomotor activity, produced muscle relaxation and  showed antianxiety activity. Conclusions: Ethanols extract of A. Aspera exhibit CNS depressant action and significant anxiolytic activity comparable to diazepam.