As the age of peritoneal dialysis continues to increase, the patient’s peritoneal function will gradually decline, as evidenced by accelerated solute transport and gradual reduction of water ultrafiltration until ultrafiltration failure occurs; once ultrafiltration failure occurs, it will directly lead to peritoneal dialysis failure. Peritonitis, biologically incompatible dialysate, residual renal function, and long dialysis age are influential factors in peritoneal decompensation. The peritoneal balance test is currently the most commonly used method to evaluate peritoneal function, but it should be analyzed in conjunction with clinical dynamics. Standardizing the prevention and treatment of peritonitis, formulating reasonable dialysis prescription, protecting residual kidney function, and applying new dialysis fluid are practical and effective intervention strategies to protect peritoneal function.