Alterations in the pattern of basic electric rhythm of the stomach and jejunum were studied in a total of 12 dogs subjected to following procedures; (a) transection and close contact repair of the entire seromuscular layer in the upper jejunum; (b) transection and close contact repair of the seromuscular layer in the stomach; (c) transection and interposition repair with alpha cyano acrylate in the stomach. Jejunal transection has resulted in permanent interruption in coupling of the basic electrical rhythm irrespective of repair procedures of the muscle layers. Gastric transection has revealed interruption in coupling of the basic electrical rhythm temporarily, but coupling phenomenon was observed in about 14 days. Gastrin transection with alpha cyano acrylate interposition has resulted in interruption in coupling of the basic electrical rhythm when the animal is maintained in fasting state. However, coupling has occurred immediately after the feeding or intragastric balloon distension. These results indicate that there exists some difference between the stomach and the jejunum in the effects of transection on electrical activities. Coupling phenomenon of the basic electrical rhythm observed in the transected stomach is probably due to an interaction of nervous system or a mechanical stimulus acting across the transection line.