Objective: To study the spasmogenic and spasmolytic properties of Terminalia chebula. Diagnostic parameter of smoothmuscle activity was used for the determination of characteristic spasmogenic and spasmolytic activity of T. chebula. Design:Experimental study. Setting: This experimental study was carried out at the Department of Pharmacology, Faculty of Pharmacy, KarachiUniversity. Period: From 2005 to 2006. Material & method: This experimental study was conducted on isolated smooth muscle ofrabbit's intestine. Segment of small intestine (jejunum and ileum) was mounted in Tyroid's solution filled organ bath with maintainedo temperature at 37 C to record dose response activity. Results: It is observed that at the dose of 1 mg/ml there is a slight decrease in theresponse (0.88 cm 0.035 cm) as compare to control (1.15cm 0.040 cm). At 10 mg/ml there is a relaxing response of smooth muscleactivity (0.85cm 0.08cm) from control (1.08cm 0.125cm). While the relaxation is prominent at the doses of 20 mg/ml (0.9cm 0.5cm)and 25 mg/ml (0.55cm 0.035cm) from control (1.4cm 0.155cm) and (1.3cm 0.07cm) respectively with (p value 0.05). The effect of-2 ethyl acetate fraction shows initially relaxation and this effect disappeared after the administration of acetylcholine 1x10 M, but fullresponse of acetylcholine is not produced due to occupancy of muscarinic receptor by the extract. Conclusions: The effect of T. chebulashowed a spontaneous decrease in the movement of smooth muscles of rabbit's intestine as compared to control experiments.