Kidney stones do not hurt but keep urinating blood may be due to the small size of kidney stones, fall into the ureter, which in turn cause damage to the mucosa of the urinary tract, manifested as blood in the flesh urine. If the stone in the renal pelvis and calyx is small, failing to cause hydronephrosis, failing to cause an increase in renal volume, not pulling the renal peritoneum and stimulating the sensory nerves, there may also be no obvious back pain. However, the stone falls into the ureter, the diameter of the ureter is smaller than the width of the renal pelvis and calyx, it moves under the action of gravity or with the process of urinary discharge, damages the mucosa of the ureter, the capillaries rupture, and there is blood from the urethra out of the external orifice, which is manifested as blood in the urine. If there are kidney stones, it is recommended to go to a professional hospital, after clarifying the cause of the disease, under the guidance of the doctor to carry out the next examination and treatment.