Several experiments on the adhesion of tenden were performed with adult rabbits, and following results were obtained. 1). Adhesion of tendon seen after removal of the paratenon was most intensive in two to three weeks. 2). The adhesion was less in the tendon preserved paratenon, which was thought to be a factor affecting the adhesion of tendon. 3). Although the adhesion was slight in the crushed tendon, for the paratenon was preserved, the fixation of two to three weeks' duration was necessary for restoration of the tendon. 4). On the prevention of adhesion the effect of wrapping tendon in living fascia or polyethylene membrane was studied comparatively. The result was better in polyethylene membrane, which prevented the adhesion perfectly. 5). It was undesirable to wrap tendon in polyethylene membrane immediately after suture or transplantation, because of its complete interception of cell permeation disadvantageous to repair of the tendon. 6). Repair of the tendon were thought to be incompatible with prevention of adhesion. It was, therefor, reasonable to intend prevention of readhesion after separation of adhesion, and best result was obtained with polyethylene membrane.