Intracompartmental pressure of leg was measured by the slit catheter technique in one hundred fifty compartments of one hundred cases; fifty were from healthy young male adults, the others were from tibial fractured patients during three years from March 1983 to Fobruary 1986. The results were as follows; 1. Slit-catheter technique was found as a accurate method for continuous pressure monitoring. 2. The range of normal pressure was from zero to six millimeters of mercury(1.45mmHg±0.85). 3. Tissue pressure was 0–15mmHg(4.03mmHg±1.83) in unaffected side of fractured patients, 4–35mmHg(14.65mmHg±2.05) in affected side of fractured patients.