Branchial fistulas are formed due to the abnormal persistence of the embryonic branchial clefts. Complete branchial fistula with internal and external opening is extremely rare. This is regarding a case of unilateral complete second arch branchial fistula and incomplete branchial fistula(branchial sinus) on other side in a 5 year old boy, which was confirmed by a  CT fistulogram of neck. The tract was completely excised and the patient was successfully treated.