PURPOSE: To obtain the connection structure of an electrically fused pipe coupling which is formed by the fused joint by removing the air interposed between the joint surfaces and the generated gas as a cause of the joint strength trouble, from the joint surface.

CONSTITUTION: Pipe members 2a and 2b made of synthetic resin are inserted into an electrically fused pipe coupling 1, and these members are heated, fused and connected by the electric conduction of a heating wire 5. The electrically fused pipe coupling 1 has the insertion fused holes 3a and 3b for inserting the pipe members 2a and 2b, leaving a tapered gap. The heating wire 5 installed at the hole surface parts of the insertion fused holes 3a and 3b is put into electric conduction, and the pipe members 2a and 2b in which the electrically fused pipe coupling 1 is inserted from the part having the smaller tapered gap to the part having the wider gap is allowed to proceed.