Primary mucinous adenocarcinoma of the urinary bladder is a rare malignancy and accounts for less than 2 % of all malignant urinary bladder tumors. This malignancy occurs more commonly in males, with a peak incidence in the sixth decade of life. Herein, we report a case of a 29-year-old male presenting with pain in the symphysis pubis, urinary frequency, and haematuria. Clinical, laboratory, and radiology findings lead to suspicion of urinary bladder malignancy with bilateral hydronephrosis and chronic kidney disease.