Obstructive urolithiasis is a fatal disorder affecting young male buffalo calves. The aim of the present study was to evaluate the efficacy of Walpole’s solution in dissolution of urethral calculi in buffalo calves with ruptured bladder in comparison to ammonium chloride. Therefore, twenty male buffalo calves aged 4-7 months admitted to the Clinic of Department of Surgery, Faculty of Veterinary Medicine, Zagazig University then diagnosed as obstructive urolithiasis with bladder rupture based on clinical, ultrasonographic, haematological and biochemical examinations. Ten apparently healthy calves with the same age were used as a control group. The affected animals were surgically treated with tube cystostomy technique and divided into two groups; Group I (n=10): orally administered ammonium chloride 200mg/kg and Group II (n=10): Local introducing of Walpole’s solution 100mL/animal. The time of resuming normal urination and urine pH intraoperatively and after recovery was measured. In Group I, 30%, 50% and 20% of animals resumed their normal urination within 3, 7 and 14 days postoperatively respectively meanwhile in Group II, 70% and 30% of animals resumed urination within 3 and 5 days postoperatively, respectively. The urine pH at the day of operation was 8.1±0.47. The observed calculis were triple phosphate crystals (n=16) and calcium carbonate calculi (n=4). After recovery, nonsig- nificant lower pH of urine in Group II (5.4±0.2) than Group I (6.7±0.14) was recorded. Consequently, in conclusion, Walpole’s solution had more efficacy to dissolute urethral calculi than ammonium chloride in buffalo calves treated with tube cystostomy