The most common diseases that cause painless hematuria are as follows: i. Various types of nephritis, especially IgA nephropathy, will repeatedly present post-infection carnal hematuria. Second, urological tumors, various malignant urological tumors will appear throughout painless hematuria, mostly seen in middle-aged and elderly people. Third, clotting disorders caused by the application of antiplatelet and anticoagulant drug overdose, such as the application of aspirin and warfarin overdose. Fourth, some times the urine is red, not caused by hematuria, such as eating certain foods rich in red pigment components, such as red heart dragon fruit, beets, etc. Fifth, a small number of patients with urinary tract infections or gynecological diseases have hematuria, which can also be painless. It is recommended to go to the hospital and register with the nephrology department to check urinary routine, urological ultrasound, coagulation function, red blood cell morphology, and urological CT if necessary.