The aim of present study was to find out the herbal drug which has potential antihistaminic properties. The ethanolic extract of cuscuta reflexa Roxb was found quite useful in showing anti histaminic activities, when tested on experimental albino rats. The rats were divided into four groups of two animals each. Group I was served as control and received water with ad-libitum but not treated and sacrificed for the observation of mast cells which were found 15.50± 2% intact and 88.20±2 % disrupted. In the II group which was treated with ethanolic extract of Cuscuta reflexa, it was noticed that when the dose of 50 mg/kg body weight were given orally with water ,the disruption of mast cells were found 35.60±2 % disrupted and intact mast cells were found 64.40±2 %. In the III group dose of 100 mg/kg body weight, the disruption of mast cells were found 27.70±2 % and intact mast cells were found 72.30±2 %. The rats of group IV received 10mg/kg of prednisolone (reference drug) orally for 4 days.