&NA;Manometric study with the use of continuous water perfusion system was performed on 50 patients with Grade III or IV hemorrhoids and for 29 patients with chronic anal fissure. Another 36 patients who had no anorectal symptoms or pathology were chosen as the control group. The maximal basal pressures for the controls, hemorrhoids, and chronic anal fissures 71.2±24.9, 85.3±27.7, and 87.4±38.8 mmHg, respectively; the maximal contraction pressures for the controls, hemorrhoids, and fissures were 132.9±44.9, 158.8±58.0, and 162.1±64.5 mmHg, respectively; the lengths of the functional sphincter of the three groups were 3.7±0.5, 3.8±0.8, and 3.9±0.6 cm, respectively. The maximal basal pressures and maximal contraction pressures of the hemorrhoid and fissure patients were significantly greater than those of the control group (ttestPvalue <0.05); whereas the functional sphincter lengths ofthe three groups showed no significant difference.