The advantages over a substitute for attaining the continuity following resection of the esophagus were experimentally compared between the jejunum and the colon in terms of changes in blood flow in the vascular pedicles under the influence of mechanical tension, induced systemic hypoxia and hypotension. Blood flow of the pedicled jejunal and colonic grafts used were measured with the use of direct collection through catheter introduced to the pedicled vessel. 1) As for tension-load added to the pedicle, the colon was much more tolerable rather than the jejunum. When a 40g tension was added to the jejunum, blood flow was remarkably reduced whereas there was no significant change in the colon even when a 100g tension was added. 2) As for the influence of induced hypoxic load, blood flow to the pedicled grafts was reduced when the arterial Po2 fell to below 70mg and Pco2 over 50mg. 3) As for the influence of induced systemic hypotensive load, it was significantly reduced to below about 30% of the normal systemic blood pressure in the similar patterns between the jejunum and the colon