In the present study hydro-alcoholic extract of Nyctanthes arbortristis was prepared using soxhlet’s apparatus. Albino rats were divided into 5 groups of 6 rats each. Group-I (Control) received distilled water 25ml/kg orally. Group-II (Standard). received Furosemide 20mg/kg orally. Group-III received hydro-alcoholic extract of Nyctanthes arbortristis 100 mg/kg, Group-IV received hydro-alcoholic extract of Nyctanthes arbortristis 200 mg/kg and Group-V received hydro-alcoholic extract of Nyctanthes arbortristis 400 mg/kg. The urine samples were collected for all the groups upto 5 hours after dosing and urine volume was measured. Urine was analysed for electrolytes (Na+, K+ and Cl-). ANOVA, Dunnet’s test and p-values were measured and data was analysed. hydro-alcoholic extract of Nyctanthes arbortristis exhibited significant diuretic activity by increasing urine volume and also by enhancing elimination of Sodium (Na+), Potassium (K+) and Chloride (Cl-) at doses of 100 and 200mg/kg. hydro-alcoholic extract of Nyctanthes arbortristis possesses significant diuretic activity.