The undergarment having urine-collection system is an external catheter apparatus. The undergarment having urine-collection system is adapted for use with a patient. The undergarment having urine-collection system is an undergarment that is formed with an elastic sheeting. The elastic sheeting is a water impermeable sheeting that collects urine as it is excreted and routes the collected urine to a catheter bag. The undergarment having urine-collection system is worn in the same manner as loin wear would be worn. The undergarment having urine-collection system comprises an undergarment, a tube, and a catheter bag. The tube provides a fluidic connection between
